Legal Memorandum (LM),Legal Opinion (LO) and the legal due Diligence (LD) is a specific subject that needs to be mastered exactly from the aspects of its functionality and usefulness. This is because the practice of law takes the capacity of reason or analysis on the problems posed by the law itself- problems of which the access will cause various polemics in the community. This requires an analysis of legal issues from different points of view ; social , political, economic and cultural background, in order to reduce or eliminate all aspects of the problems brought about by causal implicit matters contained therein.