The observation made by C. Morrey in 1938 has become a useful tool for partial differential equations. With this tool we can study the existence and regularity of solutions of partial differential equations. Nowadays, his technique turned out to be a wide theory of function spaces called Morrey spaces. Morrey spaces are now used in several branches of mathematics such as PDE and potential theory.

The main focus of this special issue will be on Morrey spaces in the various settings, on the property of the fractional integral operators, and on the related singular integral operators. The special issue will become an international forum for researchers to summarize the most recent developments and ideas in the Morrey spaces, with a special emphasis given to the observational and theoretical results obtained within the last five years. Potential topics include, but are not limited to:

• Singular integral operators and the behavior on Morrey spaces
• Function spaces arising from Morrey spaces
• Morrey spaces on metric measure spaces
• Fractional integral operators (related to Morrey spaces)
• Some recent open problems
• Predual/ dual of Morrey spaces
• Generalized Morrey spaces
• Morrey spaces on the probability spaces
• A survey article of Morrey spaces
• Morrey spaces with variable exponents

Before submission authors should carefully read over the journal’s Author Guidelines, which are located at http://www.hindawi.com/journals/jfsa/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/jfs/morrey/ according to the following timetable: