Alfresco content model is highly extensible. The custom aspects provide you flexibility to add an additional set of properties to the documents in specific spaces. You can customize the content model to suit your business needs. Using content associations you can relate one document with one or more documents. You also understood the benefits of a newly added feature called Dynamic models for dynamic customization of models without requiring a restart of the Alfresco server. In the next chapter, you will learn an important feature called Workflow using Activity and JBPM engine. This is one of the main features which will give you flexibility to fully automate your complex business processes.