Among the ferromagnetic Heusler alloys, those derived from Ni-Mn-Ga system have been widely studied owing to exciting phenomena like large magnetic field induced strain, magnetocaloric effect, magnetoresistance or high temperature shape memory effect that have been observed in them at different compositions. In order to tune the properties of the Ni-Mn-Ga alloys, one can either vary its composition or introduce other elements by substitution. Since boron has a tendency to cause second phase segregation, it is interesting to study the influence of boron on the crystal structure, microstructural, magnetic and mechanical properties of Ni- Mn-Ga alloys. Correlation of transformation temperatures and magnetic properties to microstructural alterations brought about by boron is worth being studied. A modified scheme to compute electron concentration, which can predict the martensitic transformations of ternary and quasi-ternary Ni-Mn-(Ga, Sb,Sn and Al)-(C0, Fe, In) systems.