Abstract: Harmony Search Algorithm (HSA) is a relatively new nature-inspired algorithm. HSA is a population based metaheuristic that inspired by the improvisation of jazz musicians. It evolves solutions by mimicking the musical improvisation process in searching for agreeable harmony. Many variants of HSA have proposed to solve different types of optimization problems. They vary from hybridizing some concepts of other metaheuristic approaches to enhance the HSA to taking some components of HSA and employed them to enhance the other metaheuristic approaches. This research reviews research issues of the parameter settings in HSA and application of HSA to effectively solve some complex problems.