The growth of the Internet has dramatically changed the way information is accessed and managed. The Web contains an ever growing amount of distributed, semi-structured and uncontrolled data. In this new context, we should rethink how applications couple with DBMSs. Corporate intranets allowed a tiered coupling between applications and databases. However, that model is still too constrained, and unable to accommodate the hostility, unsafety and fast pace of the Web environment. Web Applications soon, if not already, will seek to dynamically negotiate their relationship to distributed database services. Prior to accomplishing autonomous application\_to\_DBMS binding and seamless data migration, we need to devise a "lingua franca" to request and describe DBMS and database services and capabilities. Database descriptors (DBDs) are a step towards this vision. This paper presents the motivation for DBDs, their structure and architecture, examples and a use case scenario.