The technetium(V) complex [Tc(OH)O(dmpe)₂]²⁺ can be reduced by excess of toluene-3,4-dithiol (H₂tdt) to yield the technetium(III) complex [Tc(tdt)(dmpe)₂]PF₆. The product has been characterized by elemental analysis, UV/VIS spectroscopy, fast atom bombardment mass spectrometry and X-ray crystallography. It crystallizes in the triclinic space group P with Z= 2, a= 9.1508(9), b= 12.794(2), c= 13.516(2)Å, α= 93.94(1), β= 95.24(1) and γ= 108.791(9)°. The final R value was 0.037. The technetium co-ordination geometry is midway between octahedral and trigonal prismatic. Relevant structural parameters are Tc–S 2.318(6), S–C 1.738(4)Å, S–Tc–S bite angle 84.49(4)° and Tc–P 2.402(7)Å. The entire tdt ligand is planar. Electrochemical and spectroelectrochemical measurements have been made for the reversible Tc^III–Tc^II and Tc^II–Tc^I couples at –0.600 and –1.217 V respectively vs. Ag–AgCl (3 mol dm^–3 NaCl). A quasi-reversible Tc^IV–Tc^III couple was observed at +0.680 V. The properties of [Tc(tdt)(dmpe)₂]PF₆ are compared to those observed previously for related cis- and trans-[Tc(SR)₂(dmpe)₂]^+/0(R = alkyl or aryl) complexes.