A formalism is presented in which the laboratory frame photoelectron angular distribution (PAD) is expressed as a convolution of the molecular frame PAD with the laboratory frame molecular axis distribution. Molecular and laboratory frame PADs are discussed in the context of probing intramolecular dynamics in the time domain. Model calculations for a C-3v molecule are presented as an illustration of the differences between measurements in these two reference frames, and the effect of the degree of molecular alignment upon the laboratory frame measurements. Different symmetries of the orbital undergoing ionization are also considered in order to illustrate the sensitivity of PADs to nonadiabatic processes.