Some friendships happen almost accidentally.
You meet someone once, and within minutes the conversation feels easy – as though you’ve known each other far longer than you actually have.
Others take months to build. Some survive distance, life changes and years apart. Others quietly fade without either person fully understanding why.
We see this all the time at the events we run at The Great Friendship Project. Sometimes two people meet once at a games night and instantly click.
Other friendships build gradually – through seeing the same familiar faces at walks, socials and weekly activities.
Friendship can feel random. But psychology suggests it’s far less mysterious than we think.
Over the past few decades, researchers have uncovered surprisingly consistent patterns in how friendships form, deepen and last – and much of it comes down to repeated connection, shared experiences, and trust built over time.
How friendships form
Researchers studying friendship formation consistently point to three conditions that make friendship significantly more likely to develop.
1) Repeated proximity
One of the strongest predictors of friendship is simply seeing the same people regularly.
Psychologist Robert Zajonc explored this through the “mere exposure effect”: the idea that repeated exposure to people increases familiarity, comfort and trust over time.
This is something our project is deliberately designed around. Events happen multiple times per week, every week – not just to give people something to do, but to create the repeated familiarity that friendship actually relies on.
Because friendship rarely forms from one perfect interaction. More often, it develops from seeing the same people consistently enough that conversations can continue naturally over time.
2) Low-pressure interaction
Friendship is rarely built through one big conversation.
It’s usually built through smaller moments: chatting before an event starts, walking beside someone during a social walk, continuing a conversation while heading to the tube afterwards.
These low-pressure interactions matter because they allow connection to feel natural rather than forced.
We see this al the time at The Great Friendship Project. Often, it’s the in-between moments people remember most – the conversations before a walk begins, chatting during a board games break, or staying behind after an event has officially ended because nobody quite wants to leave yet.
One of the reasons adult friendship can feel harder is because modern life gives us fewer opportunities for this kind of repeated, casual interaction. We work remotely more. Spend more time online. The environments that once created friendship naturally slowly disappear.
3) Spaces for real conversation
Friendships tend to form most easily in places where conversations can move beyond surface-level small talk.
That’s why activity-based events often work so well. Walks, board games afternoons and social craft nights naturally create space for conversation to develop gradually, without the pressure of formal networking or forced socialising.
At The Great Friendship Project, we often notice that people open up most naturally while doing something alongside each other rather than sitting face-to-face in a highly pressured setting. Shared activity removes some of the performance from conversation.
And that matters, because friendship relies on emotional openness – even in small amounts.
What deepens friendship
Repeated interaction creates familiarity. What deepens friendship is openness.
Not dramatic oversharing – just conversations gradually becoming slightly more honest over time.
Psychologist Arthur Aron demonstrated this in his famous “36 Questions” experiment. Pairs of strangers who asked each other increasingly personal questions reported feeling significantly closer afterwards than people who engaged in ordinary small talk.
We see versions of this happen constantly at our activities. A conversation during a social walk shifts from “What do you do for work?” to talking about moving to London, struggling to make friends, or feeling burnt out from work.
Someone admits they nearly didn’t come because they felt nervous. Another person says they felt exactly the same.
Those moments of honesty are often where connection starts to deepen.
What sustains friendship
One of the biggest myths about friendship is that meaningful friendships should feel effortless all the time.
In reality, long-term friendships are built through repeated small acts of effort: checking in, making plans, showing up consistently.
Psychologist Caryl Rusbult developed what became known as the “investment model” of relationships – the idea that commitment grows partly through what we put into a relationship over time.
And this applies to friendship too.
This is often why people who attend regularly our activities tend to build the strongest friendships over time. Shared experiences accumulate. Familiar faces become recognisable. Eventually, the community itself starts to feel familiar too.
Why friendship matters
The Harvard Study of Adult Development – one of the longest-running studies ever conducted on human happiness – found that the quality of people’s relationships was one of the strongest predictors of long-term health and life satisfaction.
Not income.
Not career success.
Relationships.
Friendship isn’t just a “nice extra” in life.
It’s one of the foundations of wellbeing.
The takeaway
Friendship in adulthood rarely happens automatically. The environments that once created connection naturally – school, university, shared routines – often disappear.
But the encouraging part is this: friendship is not purely luck.
The research is surprisingly clear about what helps: repeated interaction, shared experiences, consistent presence, and spaces where conversations can gradually become more real over time.
That’s exactly why communities like ours exist.
And often, friendship begins far more simply than we expect. Sometimes all it takes is one conversation, one familiar face, or one decision to come back again.
