The neutral and cationic 1-tris(pyrazolyl)borate (Tp) organo-beryllium complexes TpBe(R) (R = Ph, nBu, Me, Cp, Cp*) and [TpBe(carbene)]+ (carbene = IMe, IiPr, IDipp, CAAC(Dipp)) have been synthesized. These compounds were analyzed via NMR and IR spectroscopy, mass spectrometry as well as X-ray diffraction. A comparison of the Be-C bonds in solution and the solid state revealed no significant differences in the nature of this bond. Extensive quantum chemical evaluation of the bonding within the DFT framework showed that the Be-C bonds in all cases are dative covalent.