Every year on Valentines Day, we take some time to work on our relationship. We think about our appreciation for our romantic partner, and what we can do for them to make the day feel special.

There’s no equivalent to Valentines Day for co-founders, but maybe there should be. After all, many people in small businesses spend just as much, or even more time with their business partners each week than they do with their spouse.

There are lots of parallels between how we relate to the people we choose to share our home and work lives with. In both cases, it’s important to complement each other’s strengths and weaknesses, take time to consider one another’s needs and feelings, listen and communicate well. Both types of relationship need strong foundations to weather the stresses and strains that life can throw at us.

We spoke to several members of the Sussex Innovation community about what makes the relationship with their business partner work, and what advice they would offer to anyone seeking a co-founder. Here’s what they had to say.

“As well as being co-founders, Mark and I are also in the unusual position of being married to each other,” says Maddie Henson of Henson IT Solutions. “That gives a whole different dimension to it! Neither of us had founded a company before this so it was a very new direction for us, though we had often talked of it before. For my part I would never have done it on my own as I strongly believe that you need to be able to have someone to challenge your assumptions. The other advantage it gives you is companionship. Exciting as founding a startup can be, it can also be very lonely so having someone with you on the journey is really helpful.

“In terms of advice the first thing that comes to mind is that it is important to know your fellow partner’s working style really well. Remember you are likely to be very dependent on the other person and their instincts. In our other unique situation the other big thing we have needed to be able to be is discipline in decompartmentalising our lives – work is for work and home is for home.”

“It’s important to know your co-founder really well,” says Bhavesh Busa of Jinoby. “Tariq [Karim] and I were friends and colleagues for many years before we set up our business so we have a strong relationship, which helps us during the tough times.”

“My best of piece of advice for anyone planning to go into business together is to communicate, even when it’s hard,” says Rosie Scott, co-founder of Definition Health. “What makes the relationship work is playing to each other’s strengths, recognising your weaknesses and using the unique combination to make the better version of you both. Try to avoid competing with each other!”

“Sarah [Burton, co-founder] and I have worked together for fifteen years,” says John Burton, co-founder of INSET Online. “We’re very different people, but it works because we balance each other out. Co-directors of companies should look out for each other and listen to each other. It’s sometimes hard to keep that in mind during the early days when you’re focused on the survival of the business, but you have to remember that everyone is ultimately working towards the same goal. If either of you need support from the other to reach that goal, or need to work towards it in a different way, then that’s what you should do.”

“Starting and running a business involves a degree of risk,” says Nick Thomsitt, Operations Director at One Research. “Alistair [Crombie, Managing Director] and I share similar views on risk. We tend to agree on which risks we take and how best to mitigate them. And we tend to agree on which risks we don’t want to take. This has made taking some fundamental decisions easier, and undoubtedly made those decisions better.

“Being able to cover each other’s roles, at least to an extent, has also made us more stable as company. Starting a business and making it successful is a marathon, not a sprint. Being able to support each other has made us stronger as a team and as a company. Equally, bringing different experience and different aptitudes, complementary to each other, has made us a more effective and enduring team.

“A shared sense of humour does go a long way. I mentioned that some of the choices we’ve made have been easier because of our shared assessment of risk. But there will be times when the choice facing you isn’t much better than laugh or cry. That’s when it’s good that you both plump for option one.”