We tend to imagine that strong relationships are held together by big moments. The trip, the proposal, the grand apology. In practice they are held together by something far less cinematic: a handful of small behaviours, repeated.

Researchers Laura Stafford and Daniel Canary set out to identify what those behaviours are. Studying how couples sustain satisfaction, commitment and trust over time, they identified five core relationship maintenance strategies. None of them is a grand gesture. All of them are things you could start doing this week.

1. Positivity

Being pleasant, warm and reasonably good company for the person you live with. This is not about faking cheerfulness or refusing to raise problems. It means making an effort to be someone your partner enjoys being around: complimenting them, expressing gratitude, being playful, keeping your bad mood from becoming the room's weather. Positivity is one of the most consistent predictors of relationship satisfaction in the research.

2. Openness

Talking directly about the relationship itself. Where things stand, what you need, what is working, what you appreciate. Most couples talk constantly about logistics and almost never about the relationship. Openness is the antidote to assumption and mind reading, and couples who practise it report more trust and fewer misunderstandings.

3. Assurances

Communicating that you are committed and you are staying. I am here. We will figure this out. I choose us. These matter most exactly when they are hardest to say, during stress, conflict or uncertainty. Assurances create emotional safety, and emotional safety is the ground everything else stands on.

4. Social networks

Investing in a shared social world. Spending time with each other's friends and family, and building friendships you hold in common. Couples with strong shared networks tend to be more stable, partly because those networks offer support, perspective and a sense of belonging that does not rest entirely on the two of you.

5. Sharing tasks

Taking joint responsibility for the work a shared life requires: chores, planning, admin, emotional labour, parenting. The emphasis in the research is on perceived fairness rather than an exact split, and it is one of the strongest long term predictors of satisfaction there is.

Why these five are worth knowing

Most relationship advice fails at the same point. It tells you that you should invest in your relationship without telling you what investing looks like on a Tuesday. These five are concrete enough to act on and well supported enough to trust.

You do not need to overhaul everything. Read back through the list and notice which one your relationship is thinnest on right now. Most couples know immediately. Pick that one, practise it deliberately for a couple of weeks, and pay attention to two things: how your partner responds, and how you feel about the relationship.

Relationships do not stay healthy by accident. They stay healthy because two people keep doing small things on purpose.