Methods of adhering polymeric materials to a substrate, either directly or through linker molecules, are disclosed. Structures, for example microstructures, including microwells and arrays of microwells, may be readily formed using the methods. In some embodiments, microstructures formed completely from polymeric materials are provided, making it possible to tailor the chemical and physical properties of the microstructures. For example, microwells having a bottom comprising a polar polymeric material and well sides/top comprising a non-polar polymeric material are provided. Biochemical reagents may be easily delivered to such "smart wells" because the intrinsic attraction of the well bottom for the reagents and the intrinsic repulsion between the well sides/top combine to direct the reagents to the wells.