The original stability problem was posed by S. M. Ulam in 1940 and concerned approximate homomorphisms. The pursuit of solutions to this problem, but also to its generalizations and modifications for various classes of (difference, functional, differential, and integral) equations and inequalities, is an expanding area of research and has led to the development of what is now quite often called the Hyers-Ulam stability theory. The special issue is focused on the latest achievements in that type of stability for various objects. The authors are invited to submit original research papers as well as review articles that will stimulate the continuing efforts in Ulam's type stability, its applications, and related problems. Moreover, high quality papers on solutions of functional equations and inequalities will be considered for publication in this special issue, as well. Potential topics include, but are not limited to:

• Hyers-Ulam stability of difference, functional, differential, and integral equations
• Generalized (in the sense of Aoki and Rassias, Bourgin and Găvrută) stability
• Stability of functional inequalities
• Superstability
• Stability in various (classical Banach, non-Archimedean, fuzzy, and quasi-Banach) spaces
• Direct, fixed-point, and invariant mean methods
• Stability in the sense of Ger
• Applications and related problems
• Stability on a restricted domain

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