Although Newtonian jet stability has been the object of numerous experimental and theoretical studies, the total problem of jet disintegration is by no means solved. Theories available in the literature are only applicable to low-speed laminar jets in stagnant air. In practice, the stability of a liquid jet may be influenced by the ambient medium, turbulence in the nozzle, and the extent of development of the velocity profile. None of these factors has received adequate study. This work presents the beginning of a systematic evaluation of the role played by these factors in the destabilization of a liquid jet. Correlations are presented for predicting the stability of both turbulent and high-speed laminar jets in stagnant air.