A new direct-write system for fabricating suspended microscale and sub-microscale polymer fibers has been developed and characterized. This system is capable of generating arrays of precisely-positioned fibers with controllable diameters in three-dimensional space. The driving mechanism behind this process harnesses the surface tension of liquid bridges to promote the controlled thinning of a macroscale polymer solution filament into the desired micro- or sub-microscale fiber. The correlation between fiber diameter and several experimental parameters including solution concentration, drawing rate, and fiber length was characterized using a series of viscous poly(methyl methacrylate) (PMMA) solutions. A dimensional analysis of the physics of the fiber drawing process was used to adapt this data into an empirical relationship describing fiber formation from a generalized polymer solution. This information was subsequently utilized to predict fiber diameter from several other non-PMMA-based polymer solutions with accuracy comparable to the intrinsic variation of the process itself, thereby eliminating the need to perform lengthy characterizations on new polymer solutions. (C) 2011 Elsevier Ltd. All rights reserved.