This paper presents an analysis of molecular structure based methods for estimation of properties from a process/product design point of view. Properties are classified as primary (dependent only on the molecular structure) and secondary (dependent on the molecular structure and other variables/properties). Estimation methods are classified as "reference" (accurate but computationally expensive) and "approximate" (limited application range but computationally simple). Relationships between molecular structures, properties and design have been identified and how they can be exploited in process/product design are highlighted. Finally, a discussion on how the methods for estimation of properties can be coupled to current and future integrated approaches to process/product design, is presented.