The invention discloses a process simulation in a cell processing facility. The present invention provides improved methods, facilities and systems for parallel processing of biological cellular samples in an efficient and scalable manner. The invention enables parallel processing of biological cellular samples, such as patient samples, in a space and time efficient fashion. Process simulation may be used to determine the optimal arrangement and/or quantity of cell processing equipment needed. The methods, facilities and systems of the invention find particular utility in processing patient samples for use in cell therapy.