In chemical engineering, most applications of molecular thermodynamics have been based on various forms of the van der Waals theory of fluids augmented by chemical equilibria and by concepts from other, by-now classical theoretical concepts such as the Flory-Huggins model for polymers and the Debye-Huckel theory for electrolyte solutions. "Extended" van der Waals theory remains a promising method for contributing to the solution of contemporary engineering problems. While modern developments in the theory of fluids are impressive, as yet, they have had only limited impact on engineering practice, in part, because of the widening communication gap between those who do statistical mechanics and those who design and develop chemical processes and products. To realize the large potential utility of molecular thermodynamics, both classical and modern, researchers must not only exhibit more willingness to reduce their work to practice but also to exhibit multidimensionality, i.e., to relate molecular thermodynamics to other chemical engineering disciplines such as mass and heat transfer, nucleation and chemical kinetics. While the future success of molecular thermodynamics will be enhanced by progress in its own narrow domain, the promising possibilities of applied molecular thermodynamics depend crucially on its integration within the wider domain of chemical technology.