With just 20 employees, we are looking for better discipline. Just having rules will not suffice. Theoretically, you may be able to achieve discipline for some time. But, good quality human resources will not sustain and find better openings. The low quality ones will build up their strengths over it and arm twist the management over it. Best way is to work on the basis of individual targets and timelines duly committed on paper. Availing leaves is within the rules and directly nobody can prevent it. But, proper pre-planning can be encouraged. Moreover, during festivals everybody prefers to enjoy with family. So target planning must be compiled with a clear view and understanding. In case, we have people availing leave en-masse on the same day, the trouble is much more than you feel it now.