The aim of this chapter is to consider the practical issues when combining two different imaging modalities. Starting with patient handling and measurement workflow, this chapter describes the factors that need to be considered in a hybrid environment. Ethical considerations need to take account of the potential risks associated with magnetic fields, as well as with ionising radiation. Incidental findings and data protection issues are also addressed, along with dose considerations, magnetic resonance safety, combined patient handling and measurement workflow. Finally, the ethical issues arising when operating in a hybrid environment and measuring simultaneously with two modalities are also considered.