The 4-(2'-pyridyl)-1,2,3,5-dithiadiazolyl neutral radical 1 has been prepared for use as a spin-bearing bidentate ligand. The coordination of this ligand to bis(hexafluoroacetylacetonato)cobalt affords a thermally stable complex 2. Magnetic susceptibility measurements of the crystalline complex indicate ferromagnetic coupling between the ligand-centered spin and the unpaired electrons of the high-spin Co(II).