IN THE LAST DECADE PHOTOMETRIC OBSERVATIONS BY THE HUBBLE SPACE TELESCOPE HAVE REVEALED THAT NEARLY ALL GLOBULAR CLUSTERS CONTAIN MULTIPLE POPULATIONS OF STARS. STELLAR MODELS AND ISCOHRONES HAVE BEEN USED TO INFER THE PROPERTIES OF THE DIFFERENT POPULATIONS WITH THE GENERAL CONSENSUS BEING THAT THE POPULATIONS DIFFER IN THEIR HELIUM AND LIGHT ELEMENT CONTENT. HOWEVER THE STELLAR MODELS WHICH ARE USED TO INTERPRET THE DATA DO NOT SELF CONSISTENTLY TAKE INTO ACCOUNT THE EFFECTS OF ENHANCED HELIUM ABUNDANCES ON THE STELLAR ATMOSPHERE BOUNDARY CONDITIONS AND WERE CREATED USING A PRESCRIPTION FOR CONVECTION WHICH IS SUITABLE FOR THE SUN BUT NOT FOR THE METAL-POOR STARS FOUND IN GLOBULAR CLUSTERS. WE PROPOSE TO COMBINE NEW MARCS MODELS ATMOSPHERES WITH THE DARTMOUTH STELLAR EVOLUTION CODE TO SELF-CONSISTENTLY MODEL THE MULTIPLE POPULATIONS IN GLOBULAR CLUSTERS. THESE MODELS WILL BE CREATED WITH A PRESCRIPTION FOR CONVECTION WHICH IS SUITABLE FOR METALPOOR STARS AND OUR NEW MODELS WILL PROVIDE INDEPENDENT ESTIMATES OF THE DEGREE OF HELIUM ENHANCEMENT IN THE MULTIPLE POPULATIONS OF A NUMBER OF GLOBULAR CLUSTERS A KEY CONSTRAINT ON FORMATION SCENARIOS FOR GLOBULAR CLUSTERS. FINALLY WE WILL ADOPT A MONTE CARLO APPROACH WHICH TAKES INTO ACCOUNT THE VARIOUS UNCERTAINTIES IN STELLAR MODELS (FOR EXAMPLE THE OPACITIES NUCLEAR REACTION RATES AND TREATMENT OF CONVECTION) TO DETERMINE THE UNCERTAINTY IN THE PREDICTED PROPERTIES OF THIS NEW GENERATION OF SELF-CONSISTENT STELLAR MODELS. THESE NEW MODELS WILL PROVIDE KEY CONSTRAINTS FOR MODELS OF THE FORMATION OF GLOBULAR CLUSTERS WHICH WERE AMONG THE FIRST MASSIVE OBJECTS FORMED IN THE UNIVERSE.

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