The paper extends the product form concept to networks of queues with batch arrivals and batch services with routing between queues dependent upon the batches released. The results are valid for continuous time as well as discrete time and for open, closed and mixed queueing networks. The release rates of batches use a generalised form of Kelly's service rate with the additional bonus of incorporating arrival and service intensities into the same, generalised, functional form. Special cases considered include batch releases with independent routing, discrete time queueing networks, discrete time quasireversible networks, networks with correlated routing and stochastic Petri nets.