Iron (3+) and cobalt (2+) polyorganosiloxanes were synthesized and characterized magnetically. The cobalt containing polymers were found to have a ferromagnetic ground state with a mean value of J of about 10K. The iron containing polymers demonstrated both ferromagnetic coupling with a mean J value ranging from 10 to 50K (depending on Fe concentration) and antiferromagnetic interaction with an exchange constant having an absolute magnitude of about 10 times less. Several models were developed to fit the experimental data. For both systems the best model found was the following : ion-ion coupling (5/2+5/2 for Fe and 3/2+3/2 for Co) arising from interactions within the polymeric chain, complicated by inter-chain interactions which are positive and negative for Co and Fe, respectively. A molecular field approximation was used to calculate the contribution of this interaction.