This chapter introduces the multidimensional random coefficient multinomial logit model (MRCML) which can be applied to multidimensional polytomous test items. Two examples of real data analyses are followed to demonstrates the applications of the MRCML. A detailed discussion is made of interpretation of item parameters, in comparision to those derived from their corresponding unidimensional Rasch measurement models. Finally, it provides some guidelines for constructing scoring matrices and the corresponding models to aid parameter interpretation.