The lithium salt of Me3CSiMe2NH2 reacted with halosilanes to give the bis(silyl)amines 1−3, Me3CSiMe2NHSiMe2R (1: R = H, 2: R = Me, 3: R = CMe3), which form lithium salts with BuLi. 4, the lithium salt of 1, crystallized as the trimer via the Li−N bond. Halosilanes reacted with lithiated bis(silyl)amines to give tris(silyl)amines 5−9, RSiMe2N(SiMe2Hal)SiMe2R‘ (5: R, R‘ = Me, Hal = Cl; 6: R, R‘ = Me, Hal = F; 7: R = CMe3, R = Me, Hal = Cl; 8: R = CMe3, R‘ = Me, Hal = F; 9: R, R‘ = CMe3, Hal = F). The ammonolysis of 5 and 7 led to the formation of the NH2-substituted compounds 10 and 11, RSiMe2N(SiMe3)SiMe2NH2 (10: R = Me, 11: R = CMe3). The fluorine-containing compounds (6, 8, 9) reacted with LiNH2 to give the 1,3,5-trisila-2,4-diazanes 12−14, RSiMe2−NH−SiMe2−NH−SiMe2R‘ (12: R, R‘ = Me; 13: R = Me, R‘ = CMe3; 14: R, R‘ = CMe3). 10 and 12 as well as 11 and 13 are structural isomers. 12 and 13 are the result of a 1,3-silyl group migration in solution at low temperatures. Thermally the 1,3-silyl group migration occurred above 200 °C for 10 and at 130 °C using 11. Quantum-chemical calculations on the thermal isomerization process reveal a two-step mechanism, whereas the anionic isomerization occurs via a single transition state at lower temperatures. 10 and 12 form the same lithium salt (15), (Me3SiNH−SiMe2−NLi(THF)−SiMe3)2. In the reaction of 15 with FSiMe2CMe3 or of the lithiated compounds of 13 with ClSiMe3 (Me3Si)2NSiMe2NHSiMe2CMe3 (16) was obtained (eq 8). Starting from 15, the reaction again includes a 1,3-silyl group migration from one nitrogen to the other. In the reaction of lithiated 14 with ClSiMe3 substitution occurred and 17 was obtained. Crystal structures of 4 and 15 are presented, and the mechanisms of the rearrangements are discussed.