The chapter focuses on exploring the contributions of the cognitive perspective to the meaningfulness of life (MOL) theoretical framework from the points of view of theory, assessment, and application. Meaningfulness of life is analyzed in the framework of the theory of meaning (Kreitler and Kreitler). A new meaning-based scale for the meaningfulness of life (MMOL) is presented. It includes items referring to 30 meaning-defined domains and the subject is requested to check the degree to which each may contribute to one's MOL and the degree to which each exists in one's life. The majority of domains checked as existing formed part of those checked as contributing to MOL. They were correlated positively with a measure of quality of life and an overall rating of meaningfulness in one's life. The majority of the domains checked as contributing to MOL corresponded to content domains in the individual's general Meaning Profile. The MMOL proved to be a tool with validity, providing both a general evaluation of meaningfulness in one's life and a specification of the domains of content that constitute one's MOL, thus extending Frankl's insights into the definition and manifestations of MOL.