The fate of a cell following stimulation by the prostanoid prostacyclin is cell specific, depending not only onthe ability of prostacyclin to activate the cell surface prostacyclin (IP) receptor and regulate its coupling to variousG proteins, but also on its ability to act intracellularly via the nuclear peroxisome proliferator-activated receptorfamily (PPAR). This review will highlight the different signalling options available to prostacyclin, and discuss theconsequences for cell responses.