Abstract: In a planetary gear, at least one planet wheel (9) is coupled by a freewheel (19) to the planet carrier (7), and the sun wheel (3) is coupled by a freewheel (13) to a center spindle (1) fixed to a casing. By the freewheels (13, 19), it is achieved that the gearing effect is released or non-positively bridged depending on the driving direction. When the direction of rotation is reversed, the freewheels (13, 19) in both directions of rotation block the planetary gear "solid" and thus the power transmission. One application is, e.g., in integrated starter/generator assemblies for internal combustion engines.