The tris(triphenylphosphine)copper(I) complexes [(PPh3)3CuX] for X = Cl (1), Br (2), I (3), ClO4(4), BF4(5), [(PPh3)3CuCl]烈3CN (1a), [Cu(PPh3)3(CH3CN)]X for X = ClO4(6), BF4(7), and [Cu(PPh3)3(CH3CN)]X烈3CN for X = SiF5(8), PF6(9) have been studied by solid state 31P CP/MAS NMR spectroscopy together with single crystal X-ray diffraction for compounds (6)-(9), the latter completing the availability of crystal structure data for the series. Compounds (1)-(5) form an isomorphous series in space group P3 (a 19, c 11 ũ with three independent molecules in the unit cell, all disposed about 3-fold symmetry axes. Average values (with estimated standard deviations) for the P-Cu-P, P-Cu-X bond angles and Cu-P bond lengths in compounds (1)-(3) are 110.1(6)ଠ108.8(6)ࠡnd 2.354(8)Šand 115.2(6)ଠ102.8(9)ࠡnd 2.306(9)Šfor compounds (4) and (5). For the acetonitrile solvated compound (1a), the corresponding parameters are 115(4)ଠ103(3)ࠡnd 2.309(3)Ů The solid state 31P CP/MAS NMR quadrupole distortion parameters, dCu, for (1)-(3) and (1a) are all less than 1 נ109 Hz2, despite the changes in donor properties of the halide in (1)-(3), and the coordination geometry of the P3CuX core in (1a). Change of anion to ClO4- and BF4- in compounds (4) and (5) results in a significant increase of dCu to 4.4-5.2 109 Hz2 and 5.2-6.0 נ109 Hz2, respectively. Compounds (6) and (7) crystallise as isomorphous [Cu(PPh3)3(CH3CN)]X salts in space group Pbca, (a 17.6, b22.3, c24.2 ũ, while compounds (8) and (9) crystallize as isomorphous acetonitrile solvated salts [Cu(PPh3)3(CH3CN)]X烈3CN in space group P(a 10.5, b 13.0, c19.5 Ŭ 104, 104, 94੮ The P3CuN angular geometries in all four compounds are distorted from tetrahedral symmetry with average P-Cu-P, P-Cu-N angles and Cu-P bond lengths of 115(4)ଠ103(4)ࠡnd 2.32(1)Ŭ with dCu ranging between 1.3 and 2.5 נ109 Hz2. The solid state 29Si CP/MAS NMR spectrum of the pentafluorosilicate anion in compound (8) is also reported, affording 1J(29Si, 19F)= 146 Hz.