Topology control in a wireless ad-hoc network allows better spatial reuse of the wireless channel and network resources. The existing topology control algorithms tend to optimise network power usage by keeping the topology connected but do not take the network application requirements into account. Mission critical applications which require explicit end-to-end bandwidth and delay guarantees may not find enough resources in the network with the existing network topology. We have devised a topology control algorithm for mission critical applications (TCMCA) in wireless ad-hoc networks, which adapts the network topology to improve the available resources for a set of mission critical applications (high priority services) in a network. TCMCA is a source based algorithm where topology control decisions are made on distributed network knowledge. The performance of TCMCA is evaluated for a static wireless network and compared against algorithms such as connect, LINT and full power transmissions. We demonstrate that TCMCA shows better support for mission critical services for varying number of mission critical applications in the network.