In this investigation, new stability parameters and their relative sensitivity for alkaline earth based lanthanum borosilicate glasses have been developed. In addition to this, the variation of the proposed stability criteria has been studied as a function of heating rate as the characteristic temperatures of various glasses studied show a great dependence on heating rate. The stability parameters include the inflection temperature (Tf) obtained from derivative differential thermal analysis (DDTA). The interval between Tf and glass melting temperature (Tm)/glass crystallisation temperature (Tc) has been taken into account while proposing the new stability criteria. The parameter, which shows the greatest relative change while moving from one glass system to another has been used to determine its sensitivity. Continuous heating transformation (CTH diagrams have been constructed to gain insight into the thermal stability.