Have regular management meetings. You're not just programmers any more, someone will be better at project management. Someone will know accounting and budgeting and forecasting. Someone will be better at sales. Someone is the people person who can go in a calm a client's nerves when they're upset.
Someone is good at hiring the right people.
Someone is a better writer and can develop marketing materials. If you're missing a skill set, look around. Spouses have a vested interest in your success and are a great resource for rounding out the company. In my husband's company, spouses have done graphic design, written proposals, done data entry, helped move, done space planning, built databases, trained office staff, provided legal advice, and provided accounting and forecasting services. Friends have built and hosted the web site.