In the last two decades, new optimization algorithms have become popular, and algorithms such as harmony search and firefly algorithms have shown their superior efficiencies. For example, harmony search has been used in many areas in engineering optimization. At the same time, significant progress has been made concerning a wide range of nature-inspired algorithms. Metaheuristics and swarm intelligence are becoming widely used for design optimization. Metaheuristic algorithms tend to be nature inspired and more often swarm based and have permeated almost every area of engineering and industry. It is timely to edit a special issue to review the latest developments in both theory and applications about these algorithms.

We invite authors to contribute original research articles as well as review articles on recent advances in harmony search and nature-inspired algorithms with emphasis on the mathematical analysis of algorithms and their applications in engineering optimization. Potential topics include, but are not limited to:

• Harmony search
• Cuckoo search
• Firefly algorithm
• Particle swarm optimization
• Swarm intelligence
• Mathematics of metaheuristics
• Engineering optimization

Before submission authors should carefully read over the journal's Author Guidelines, which are located at http://www.hindawi.com/journals/jam/guidelines/. Prospective authors should submit an electronic copy of their complete manuscript through the journal Manuscript Tracking System at http://mts.hindawi.com/submit/journals/jam/hsni/ according to the following timetable: