This research work examined the impact of strategic management as a tool of achieving an effective and efficient merger and acquisition. The companies are established by their owners as an investment centre to generate return on their investment through their growth strategies. i.e. a combination of two companies into one larger company, which aims at minimizing cost, and at the same time maximizing profit and wealth of the shareholders of the company. Regrettably, not only have most of these companies failed to achieve these laudable objectives, but also some of them had disappeared from business of economic environment after their merges and acquisitions. Several reasons have been adduced for the abysmal performance of some of these companies. Prominent among these had been the inability by those at the helm of affairs i.e. management to recognize the impact/role of strategic management and apply same to the operations of their companies. To carry out this research, both primary and secondary data were extensively collected, secondary data were extensively used. Copies of questionnaires were administered to the respondents of Nestle and Liver Brothers Plc under study. Data collected were analyzed by the use of tables, simple percentages amid chi-square. Findings were made in the course of the study, prominent among them included. That, strategic management played a very important role in the success, growth and survival of the companies, particularly where mergers are concerned.