Showing that the components of the system have been correctly installed and work is an important foundation in the overall CDS validation. Typically, third parties including the IT department and the supplier will carry out much of this work. However, the responsibility for the work planning, supervision and checking remains with the CDS validation team. The phasing of the work should be defined in the validation plan for the system and should be formulated following discussions with the CDS supplier, IT and the laboratory staff. Depending on the size of the system there may be a need to phase the installation of components partly to avoid disrupting the laboratory work, but also due to availability of staff from the supplier and IT.