Abstract: Self-contained, preprogrammable downhole well data recorder and method of use thereof, the recorder having the external configuration of a conventional sidepocket gas lift valve and being placeable and retrievable from a conventional gas lift sidepocket mandrel by a conventional valve positioning tool. The recorder monitors and collects fluid dynamics data downhole during well operations, such as stimulation, production and multi-zone well completions, without impeding fluid flow. Programming can involve selective actuation of one or more of the sensors intermittently for at least thirty days. After retrieval of the recorder, fluid dynamics data stored in memory is outputted to external equipment for analysis in a manner known per se.