In the recent time the interest about UAL is greatly increased partly because with this technique it seems possible to guarantee constant and sure results, and partly because the machine manufactures have worked to make this procedure well known in a complete and full way. With the major diffusion of the UAL the casisistic have increased too, the indications have widened, the complications began to show up, and the limit of the procedure have begun to be defined. In these years the instrumentation constantly evolved, from the initial devices designed for plastic surgery manufactured by SMEI, until the more recent models on the actual market. Purpose of this study is to compare the considerations made when the senior author firstly experienced UAL 14 years ago, with the actual orientations. The Authors refer about their experience , exposing a comprehensive casistic developed with the use of different machines: starting with the first ultrasonic liposuction performed with neurosurgical instruments, to follow with 1st generation devices for lipolisis , until the recent sophisticated machines that allow a more wide use of the UAL. The results of the studies done in these years with biochemical and morphologic techniques on some peculiar aspects of UAL versus traditional techniques are shown.