In order to investigate electronic and magnetic properties of permanent magnets, we have performed self-consistent electronic structure calculations on compounds of rare-earth and transition metals, such as $SmCo_{5},;NdB_{6},;NdFe_{5},;NdFe_{4}B$. Employing the local density LMTO(linearized muffin tin orbital) band method, we have obtained the ground state parameters, such as band structures, density of states, Stoner parameters, and magnetic moments. We have also investigated interactions between d,f-electrons of Nd, Sm rare-earths and d-electrons of Fe, Co transition metals, and the s,p electrons of boron and explored effects of such interactions on the bonding mechanism and the electronic and magnetic structures in these rare-earth compounds.