The syntheses of the 1,3,5-trimethyl- and tri-tert-butyl-1,3,5-triazacyclohexane-supported imido complexes [M(NR)(R' 3 tach)Cl 2 ] (M = Ti or Zr (NMR only); R = Bu t or 2,6-C 6 H 3 Pr i 2 ; R' = Me or Bu t ) are reported, along with that of the thermally robust dibenzyl derivative [Ti(NBu t )(Me 3 tach)(CH 2 Ph) 2 ]. The tert-butylimido ligand in [Ti(NBu t )(Me 3 tach)Cl 2 ] undergoes exchange with ArNH 2 (Ar = 4-C 6 H 4 Me or 2,6-C 6 H 4 Me or 2,6-C 6 H 3 Pr i 2 ) to form the corresponding arylimides [Ti(NAr)(Me 3 tach)Cl 2 ]. The Me 3 tach ring in [Ti(NR)(Me 3 tach)Cl 2 ] undergoes slow exchange with Bu t 3 tach or Me 3 tacn (1,4,7-trimethyl-1,4,7-triazacyclononane) to give the ring-exchanged products [Ti(NR)(Bu t 3 tach)Cl 2 ] and [Ti(NR)(Me 3 tacn)Cl 2 ], respectively. The complexes [Ti(NR)(Me 3 tach)X 2 ] (R = Bu t or 2,6-C 6 H 3 Pr i 2 ; X = Cl or CH 2 Ph) exhibit room-temperature dynamic NMR behaviour via an unusual trigonal twist of the facially coordinated Me 3 tach ligand, and the activation parameters for these processes have been measured and are discussed. The X-ray structures of [Ti(NR)(Bu t 3 tach)Cl 2 ] (R = Bu t or 2,6-C 6 H 3 Pr i 2 ) and [Ti(NBu t )(Me 3 tach)(X) 2 ] [X= Cl or CH 2 Ph) are reported. Me 3 tach and Bu t 3 tach = 1,3,5-trimethyl- and tri-tert-butyl-1,3,5-triazacyclohexane, respectively.