Documentation is an important part of the captured knowledge of a software project, providing a flexible and effective way of recording informal contents. However, maintaining documentation's consistency requires a considerable effort. Existing solutions encompass different tools and approaches that support the process of creating, evolving and using documents and other artifacts derived from the software development process. Based on existing literature and expertise, we have identified the key problems and solutions for documentation consistency. In concrete, four distinct patterns and their relations were identified, which are here described --- Information Proximity, Co-Evolution, Domain-Structured Information and Integrated Environment.