Assuming you are structured as a limited company rather than a Partnership then one of the best ways to incentivise staff in a professional services type business such as a consultancy or an agency is to give them an equity award.

If the company generates dividends which are paid out to shareholders then a SIP can be an ideal way to align the success of employees with the owners. Or if growing the business in the hope of a sale is the business plan then an option scheme such as EMI might be a good fit.