The process of building a new database relevant to some field of study
in biology involves transforming, integrating, and cleansing multiple
external data sources, as well as adding new material and annotations.
Creating and maintaining these ``view'' databases raise a number of
problems: 1) How can we specify and implement the transformation and
integration from the underlying source databases to the view database?
2) How can we automate the refresh process?  3) How can we track the
origins or ``provenance'' of data?  In this chapter, we discuss these
phases of creating and maintaining curated view databases and contrast
solutions where appropriate.