Abstract The aim of this thesis is to show how numerous organizations such as CGI Consultant attempt to introduce BI-Solutions through IT and other operational methods in order to deal with large companies, which want to make their competitive market position stronger. This aim is achieved by Gap Analyzing in the BI roadmap and available Data Warehouses based on one of the company projects which were handed over to CGI from Lithuania. The fundamentals in achieving the BI-Solutions through IT, which has built the thesis methodology by research are, data warehousing, content analytics and performance management, data movement (Extract, Transform and Load) and CGI BI methodology, business process management, TeliaSonera Maintenance Management Model (TSM3) and AM model of CGI in the high level. The part of the thesis basically requires some research and practical work on Informatica PowerCenter, Microsoft SQL Server Management Studio and low level details such as database tuning, DBMS tuning implementation and ETL workflows optimization.   Keywords: BI, ETL, DW, DBMS, TSM3, AM, Gap Analysing