  We apply the restricted-path-integral (RPI) theory of non-minimally
disturbing continuous measurements for correct description of frictional
Brownian motion. The resulting master equation is automatically of the Lindblad
form, so that the difficulties typical of other approaches do not exist. In the
special case of harmonic oscillator the known familiar master equation
describing its frictionally driven Brownian motion is obtained. A thermal
reservoir as a measuring environment is considered.
