Recent literature relating to turbulent fluidization is reviewed and earlier literature reassessed in the light of present knowledge in an attempt to resolve the confusion and controversy surrounding the subject. There is mounting evidence and support for the view that the velocity U-k at which the amplitude of bed pressure fluctuations levels off heralds the onset of dilute transport, as suggested by Rhodes and Geldart, rather than the onset of the turbulent fluidization regime as proposed by Yerushalmi and co-workers. There is also now considerable agreement that the velocity U-c, at which the amplitude of bed pressure fluctuations is maximum, marks the beginning of a regime of transition from bubbling or slugging to transport. This transition regime is now widely referred to as the turbulent fluidization regime. The characteristic structure of the bed in this transition regime and the mechanism for the transition are still unclear.