With the increase in commercial off-the-shelf components being used to produce complex systems the safety engineer is presented with a variety of standards on which to base a cohesive safety case. Low volume suppliers also do not have the leverage with suppliers to produce high integrity versions of components and sub-systems. Compressed timescales do not allow for reverse engineering to allocate an integrity level. This paper discusses a risk management process based around accident sequencing. This uses event trees as a framework on which to place controls or mitigations conforming to a variety of standards.