In a multiproject, how to order the execution of projects

In a multiproject, how to order the execution of projects. Ex:Have ProjectA,ProjectB and ProjectC. ProjectC has to build first and then ProjectB and ProjectA. Please help me on how to order the execution of projects.

The order is dictated by the dependency graph. For example if A depends on B and C, then B and C will be executed before A.

Even after mention the dependencies,Projects are not building in a proper manner.

Thanks i got the solution.