Until comparatively recent times, the distinction between direct and indirect participation in hostilities was comparatively uncontroversial. Now, in the battlespace, there are many different actors. The regular armed forces sometimes seem to be almost in a minority. The complexity of weaponry has led to a growing number of civilian contractors hired to maintain, repair and in some cases even operate equipment. Unmanned aerial combat vehicles can be operated by personnel situated thousands of miles away from the conflict area. The cost of maintaining military personnel has also led to the contracting out of many support functions, particularly logistics. The merging of front lines and rear areas has meant that rear area security, often in the past carried out by civilian personnel, has now developed into a major industry so that private military and security companies bid for contracts all over the world in areas where they will be operating in areas of conflict.