The reaction of Me5C5GeCH(SiMe3)2 with LiC-(SiMe,)3 affords (Me3Si)3CGeCH(SiMe3)2 (2), the first unsymmetrically substituted dialkylgermylene, which is stable at ambient temperature. In the solid state, the germylene 2 is monomeric, whereas Lappert's germylene [(Me3Si)2CH]2Ge (1) shows a dimeric structure with a Ge=Ge double bond. Steric effects of the additional trimethylsilyl group in 2 are responsible for these drastic changes in the structure. The germylene Me3SiCH2GeCH(SiMe2)2 (3) decomposes at about -20° C.