The current status and apparent trends in formation evaluation are reviewed. There are at present well over two dozen borehole measurements available for formation evaluation encompassing cuttings samples, cores, borehole fluid logs, wire line logs and productivity and fluid flow tests. Some twenty major applications in petroleum engineering are realized by use of this array of measurements. The predominant application continues to be estimation of recoverable hydrocarbon volumes, but other important applications in connection with exploration, exploitation, and well completion are also realized.