A Facebook Group labeled “private” still shows up in search results inside Facebook, still lets Meta’s algorithm decide who sees what, and still leaves a permanent record on a platform you don’t control. For a mastermind group, where ten founders talk openly about real revenue numbers, real failures, and real doubts about whether the business survives the year, that’s not private enough.
The group needs a space that’s genuinely invisible to everyone outside it, not just locked. BuddyNext runs on your own WordPress site, which means the mastermind space you build is invisible to search engines, invisible to non-members browsing your site, and entirely under your control, not a platform’s. There’s no account rep who can change the rules, no policy update that suddenly makes member data visible to advertisers, and no risk of the whole group disappearing because a platform shut down or pivoted its product.
This guide walks through setting up a founders-only mastermind community: secret spaces, an invite-only structure, private messaging for accountability check-ins, and member profiles built for peer matching rather than public discovery.
Last updated: 6 November 2026
Table of Contents
- By the numbers
- Why “Private” Isn’t the Same as Secret
- Space Visibility: What Each Setting Actually Does
- A Hundred Years of Mastermind Groups
- Step 1: Create a Secret Space
- Step 2: Build an Application or Invite Process
- Step 3: Set Up Member Profiles for Peer Matching
- Step 4: Use Private Messaging for Accountability
- Step 5: Moderate for Trust, Not Just Spam
- Step 6: Structure the Rhythm
- Handling Membership Turnover
- Mastermind vs Other Community Formats
- Real-World Scenario: A 16-Founder Peer Group
- Common Mistakes
- FAQs
- Sources
Research on peer-advisory group structure consistently points to a specific sweet spot: 8 to 10 participants, meeting regularly, with rotating leadership. Larger groups dilute the trust and airtime each member needs; smaller groups run out of perspective. That’s a real constraint worth designing the platform around, not an afterthought.
By the numbers
The online community platform market was valued at USD 6.50 billion in 2025 and is expected to reach USD 15.20 billion by 2033, a 10.2% annual growth rate, according to Verified Market Research (definitions vary between research firms).
Why “Private” Isn’t the Same as Secret
Most community platforms offer one flavor of restriction: a login wall. Anyone can see the group exists, see its member count, sometimes see its name and description, and request to join.
For a support forum or a paid course community, that’s fine, visibility helps people find you. For a mastermind group, visibility is the opposite of what you want. Members are discussing cap tables, layoffs they’re considering, health issues affecting their ability to run the business, conflicts with co-founders. The group needs to not exist to anyone who isn’t already in it.
A genuinely secret space means: it doesn’t appear in site search for non-members, it doesn’t appear in a “browse spaces” directory, and a non-member navigating directly to its URL gets a 404 or an access-denied page that doesn’t even confirm the space exists. That’s a meaningfully different privacy model than “private, request to join,” and it’s the one a real mastermind group needs.
Space Visibility: What Each Setting Actually Does
Before configuring anything, it helps to see the three visibility tiers side by side, since the terminology (“private” especially) gets used loosely across different platforms:
| Setting | Appears in search/directory | Who can join | Right for a mastermind? |
|---|---|---|---|
| Open | Yes | Anyone, instantly | No |
| Private / request-to-join | Yes, existence and member count visible | Anyone who requests and gets approved | Still exposes the group’s existence |
| Secret / invite-only | No, invisible to non-members | Only people manually added | Yes, this is the correct setting |
A Hundred Years of Mastermind Groups
The term “mastermind group” was coined by Napoleon Hill in his 1925 book The Law of Success, and elaborated further in 1937’s Think and Grow Rich.
Hill studied the practice among a specific set of figures he considered successful by the standards of his time, including Henry Ford, Thomas Edison, Andrew Carnegie, and John D. Rockefeller, and documented how structured peer input accelerated their thinking in ways solo decision-making didn’t. A century later, the format is still built around the same core mechanic: a small, trusted, consistent group where members bring real problems and get real input, not a broadcast audience watching a thought leader perform expertise.
A mastermind group isn’t a networking event with extra steps. It’s a small, closed circle where the value comes specifically from what members are willing to admit out loud, which only happens when the room is genuinely safe.
Two structural variants exist in practice:
- Individual-success model: each session centers on one member’s specific problem, with the rest of the group advising in turn.
- Collective-success model: the group works toward a shared goal or shared accountability metric together, rather than rotating focus member-by-member.
Decide which model fits your group before building the space, since it affects how you structure recurring sessions and what the discussion format should look like inside it. A group of founders at wildly different company stages tends to work better under the individual-success model, since a Series A founder’s “shared goal” isn’t the same as a pre-seed founder’s. A group of founders at genuinely similar stages, say all mid-size SaaS companies targeting a specific revenue milestone, can work well under the collective-success model, where the group tracks one shared metric together. Neither model is objectively better, the right choice depends entirely on how similar your members’ current situations actually are, which is itself one more reason the application step in Step 2 matters so much.
Step 1: Create a Secret Space
In BuddyNext, spaces have a configurable join type: open (anyone can join), request-to-join (visible, requires approval), or invite-only/secret (invisible to non-members, visible only to people already added). For a mastermind group, use the most restrictive setting your installation offers.
Name the space something that doesn’t broadcast its purpose in a way that would be awkward if a screenshot leaked. “Founders Circle” reveals less than “Q3 Layoff Planning Group,” even though members will obviously discuss whatever they need to once inside.
Set a parent space only if you’re running multiple mastermind cohorts under one umbrella (e.g. a “Founders Circle Q1 2026” and “Founders Circle Q3 2026” as sub-spaces of a top-level “Founders Circle” space) so alumni can see past cohorts without current-cohort members needing access to older conversations.
Step 2: Build an Application or Invite Process
A mastermind group’s value depends entirely on member quality and fit, so the entry process matters more here than for an open community.
The realistic options on a self-hosted setup: a manual invite-only flow where you personally add each member (best for the first cohort of 8-10, where you want full control over composition), or a simple application form (a WordPress form plugin, not a public join button) that routes to you for manual approval before you add someone to the secret space.
Either way, resist the urge to make this self-serve. The whole point of secret spaces is that you decide who’s in, not an algorithm or a first-come-first-served queue. Document your actual selection criteria even if you never publish them: company stage, industry, revenue range, whatever makes peers genuinely comparable to each other. A mastermind of a pre-seed solo founder and a 200-person Series C company doesn’t give either person useful peer input; matched stage and scale is what makes the advice land.
A short written application (five or six questions, nothing lengthy) also does useful filtering work before you even review it, someone unwilling to spend ten minutes describing their business and what they’re hoping to get from the group is unlikely to show up consistently once they’re in. Treat the application itself as a light commitment signal, not just an information-gathering form.
Step 3: Set Up Member Profiles for Peer Matching
Standard community profiles optimize for public discovery: bio, avatar, social links. A mastermind group needs profile fields that help members understand who else is in the room and what they’re dealing with: company stage, industry, current headcount, the specific challenge they joined to work on.
Configure custom profile fields for this rather than relying on a generic bio field, and make these fields visible only within the secret space, not on a public-facing member directory.
Step 4: Use Private Messaging for Accountability
Group sessions (whether weekly or monthly) are where the group advises, but the accountability that makes a mastermind actually change behavior happens between sessions.
Set up direct, private messaging between members (or between a member and an accountability partner assigned from within the group) so people can check in on specific commitments made during the last session without waiting for the next one. Some groups formalize this with a specific accountability-partner pairing that rotates each cohort; others leave it informal. Either way, the private messaging layer needs to exist and be easy to find, not buried three clicks deep.
Step 5: Moderate for Trust, Not Just Spam
A mastermind group’s moderation problem is different from a public forum’s. You’re not filtering spam or off-topic posts, you’re protecting the psychological safety that makes people willing to admit a real problem out loud.
A single member who’s dismissive, competitive, or shares something outside the group can quietly end the group’s usefulness even if nothing is ever “reported.” Set clear ground rules at onboarding (confidentiality expectations, no recording sessions, no sharing specifics outside the group), and treat a ground-rule violation as a removal-worthy offense, not a warning. The group’s value is entirely dependent on every member trusting every other member, and that trust doesn’t survive a second chance after a real breach.
As the organizer, resist the urge to moderate lightly just because the group is small and self-selected. A small group actually needs clearer, more explicit ground rules than a large one, since there’s no critical mass of other voices to dilute the damage a single bad actor can do.
Step 6: Structure the Rhythm
Set a recurring session cadence (weekly works for an intensive group, monthly for a lower-commitment one) and use the space consistently between sessions, not just for scheduling.
A dedicated discussion thread per session where members can post updates before the live call saves real time, people arrive having already read each other’s updates instead of spending the first 15 minutes catching up. If your mastermind group runs toward the individual-success model, rotate whose problem gets the session’s focus; if it’s the collective-success model, use a recurring thread to track the shared goal’s progress over time.
Handling Membership Turnover
Every mastermind group eventually loses a member, someone’s company gets acquired, they shift industries, or the group simply stops being the right fit for where they are now. Plan for this before it happens rather than scrambling the first time it does.
Decide upfront whether departing members become “alumni” with read-only access to past conversations (useful if the historical discussion has ongoing reference value) or are removed entirely (simpler, and often the safer default for a group discussing sensitive business details). If you offer alumni status, create a separate alumni-only secret space rather than leaving former active members inside the live group, since an alumnus’s presence changes what current members are willing to say.
Backfilling an open seat deserves the same manual-review rigor as the original cohort, don’t let group momentum or a current member’s casual referral skip the fit-check that made the original group work in the first place. A mismatched addition, even one well-intentioned, can quietly change the room’s dynamics for everyone else.
Mastermind vs Other Community Formats
It’s worth being clear about what a mastermind space is NOT, since the term gets used loosely. Here’s how it compares to the other formats a self-hosted community commonly runs:
| Format | Typical size | Visibility | Primary goal |
|---|---|---|---|
| Mastermind | 8-10 | Secret | Peer accountability, real problems |
| Mentorship pairing | 2 (1:1) | Private messaging only | Guided, asymmetric advice |
| Investor/dealflow network | 20-200+ | Gated, directory-based | Deal discovery, filterable network |
| Public community | Unlimited | Open | Broad engagement, discovery |
Real-World Scenario: A 16-Founder Peer Group
Picture a startup community operator who wants to offer a mastermind benefit to the most engaged members of a larger public community. Instead of a generic “VIP” badge, they create a secret space, handpick 16 founders across two cohorts of 8 (following the research-backed 8-10 participant range), and build a short application asking about stage, industry, and specific current challenge.
Member profiles surface company stage and industry so peers can quickly see who’s comparable before a session. A private messaging layer lets accountability partners check in between the group’s biweekly calls.
Six months in, the group runs almost entirely itself inside the secret space: members post updates before each call, reference past sessions in the space’s history, and use private messages for the accountability check-ins that actually change behavior. None of this is visible to the broader community, which is precisely the point. The mastermind’s value comes from members trusting that what’s said there stays there, and a platform the operator controls, not a third party, is what makes that trust credible in the first place. When one founder’s company gets acquired eight months in, the operator moves them to the alumni space rather than removing them outright, since the group had already agreed historical context was worth preserving for the remaining members.
Common Mistakes
- Making the group too big. Research and practice both point to 8-10 as the functional ceiling before airtime and trust dilute.
- Using “private” instead of truly secret. A request-to-join space that’s merely locked still signals its existence to everyone browsing your site.
- Self-serve applications with no manual review. Composition quality is the entire value proposition; don’t automate away the one decision that matters most.
- No clear confidentiality ground rules at onboarding. Set expectations before the first session, not after a breach.
- Treating the space as scheduling-only. Between-session engagement (updates, accountability check-ins) is where behavior change actually happens.
- Mixing mismatched company stages. A pre-seed founder and a Series C operator rarely give each other useful peer advice.
- No plan for membership turnover. Decide alumni-access policy before the first member departure, not during it.
Summary
A mastermind group lives or dies on trust, and trust depends on genuine privacy, not a login wall with a public sign on it. Building one on BuddyNext means a secret space invisible to non-members, a manually reviewed entry process that protects composition quality, profile fields built for peer matching instead of public discovery, private messaging for between-session accountability, moderation focused on protecting psychological safety rather than filtering spam, and a clear plan for the membership turnover every group eventually faces.
Get those pieces right and the format that’s worked for a century, since Napoleon Hill first documented it among a handful of early-20th-century industrialists, still works for a group of founders meeting on your own WordPress site today.
FAQs
1. What’s the difference between a “private” space and a “secret” space?
A private, request-to-join space is still discoverable, non-members can see it exists and ask to join. A secret space is invisible to non-members entirely, it doesn’t appear in search, directories, or a direct URL visit for anyone not already added.
2. How many members should a mastermind group have?
Research on peer-advisory structure points to 8-10 as the sweet spot, large enough for varied perspective, small enough that everyone gets real airtime and trust holds.
3. Should the application process be open to anyone?
No. Composition quality is the core value of a mastermind group. Keep the application manually reviewed, or invite-only, rather than self-serve.
4. Can members find the mastermind space through the site’s normal search?
Not if it’s set up correctly. A genuinely secret space is excluded from site search and space directories for anyone who isn’t already a member.
5. What should member profiles show inside a mastermind space?
Fields useful for peer matching and context: company stage, industry, team size, current challenge, rather than public-facing bio/social-link fields meant for discovery.
6. How is accountability actually tracked between sessions?
Through private messaging, either informal check-ins or a formalized accountability-partner pairing that rotates each cohort, used between the group’s scheduled live sessions.
7. What happens if a member breaks confidentiality?
Treat it as removal-worthy, not a warning. The group’s entire value depends on every member trusting every other member completely; that trust rarely survives a second chance after a real breach.
8. Should sessions be recorded?
Most mastermind groups explicitly prohibit recording, since the psychological safety that makes people share real problems depends on knowing nothing leaves the room (or the space) in a permanent, shareable form.
9. Can I run multiple mastermind cohorts on the same site?
Yes, structure each cohort as its own secret space, optionally nested under a parent space, so cohorts don’t see each other’s conversations while you maintain one overall community.
10. Does a mastermind group need a different platform from the rest of my community?
No. The same self-hosted platform works, since you control the visibility settings directly, rather than depending on a third-party SaaS’s definition of “private.”
11. How is a mastermind group different from a mentorship program?
Mentorship is asymmetric, usually one experienced person guiding one less-experienced person. A mastermind is peer-to-peer among people of comparable stage, where everyone both gives and receives advice.
12. What’s a realistic timeline to launch a mastermind group on a new secret space?
For an existing community with an engaged member base, identifying and inviting 8-10 founders, setting up the secret space and profile fields, and running a first session can realistically happen within two to three weeks.
13. What happens to a departing member’s access to past conversations?
That depends on your alumni policy, decided in advance. Some groups revoke access entirely on departure; others move former members to a separate, read-only alumni space so current discussions stay fully private from anyone no longer active.
14. Should a backfill replacement go through the same vetting as the original cohort?
Yes. Skipping the fit-check for a casual referral or a currently-convenient candidate is one of the most common ways a previously well-functioning mastermind group quietly loses what made it work.
Sources
Interesting Reads:
How to Make Your WordPress Community Private and Members-Only with BuddyX
How to Build a Professional CE Community for Healthcare Professionals on WordPress