Simple heteroclinic networks are those made of simple cycles: cycles such that the connections between equilibria are contained in 2-dimensional invariant spaces. I shall present some results about how these cycles can be put together to form a network. Then, using the notion of stability index, I shall look at the stability of the cycles in the network and the stability of the network itself. The stability index can be calculated with respect to each cycle and with respect to the network. These two types of stability index provide additional information about the dynamics near the network.