The Ministry of Finance and Public Credit in Colombia has led to our financial instruments that have boosted the market debt public in Colombia through TES (Treasury Bonds Government). This has allowed different financial entities to form investment portfolios whose main asset are the Colombian bonds. It is therefore essential to know and understand nature, functionality and valuation of these instruments. In this document we see the TES rate fixed in colombian pesos is an instrument of the Colombian capital market. This article explores the development and study of this asset and development tools recognized for its assessment, both at the market national and international. This study aims to investigate the technical financial aspects of this financial title, in order to open the discussion on the creation of instruments novel in the public stock market of public debt in Colombia such as the Derivatives.