Enterprise Information Integration (EII) is a process that provides a single interface and data representation to make heterogeneous data sources appear as a single homogeneous source. EII faces challenges as data can be stored in various formats across different systems. Technologies like ADO.NET and JDBC help access these different data sources. EII architecture supports various data sources, SQL queries across sources, and views of integrated data. EII aims to integrate both structured and unstructured enterprise information for uses like reporting, data warehousing, and applications. Commercial tools like WebSphere Studio and WebSphere Information Integrator provide EII capabilities.