Using the artificially-defined broad term, meta-knowledge, we entail notions originating from distinct communities such as AI and SE. The most widely used are: ontologies and PSMs from the AI community and, recently, Experience Bases/Experience Factories from the SE discipline. In recent years the benefits of using meta-knowledge have informally praised in many publications and fewer applications. In this talk I will identify pragmatic issues which should be taken into account when we apply meta-knowledge. I will focus on the benefits(or otherwise) of meta-knowledge in the area of system's design, specifically, enhancing the reliability of a system and improving its reuse potential. In particular, I will discuss factors related to cost of construction and/or maintenance, familiarity with a meta-knowledge component, stability of meta-knowledge, level of formality, and evaluation issues. Whenever applicable, I will present example cases founded in the literature to illustrate how those benefits were realized. Finally, we shall discuss future research roots and speculate on the amalgamation of similar notions founded in KE and SE communities.