Nowadays Information Technology Services Management (ITSM) has become strongly needed for every kind of organizations providing IT services for customers or for themselves. However, existing models (as CMMI-SVC, ITIL or ISO/IEC 20000) are strongly difficult to implement on very small organizations. The aim of this article is to propose an ITSM model which can be applied in very small organization. Our methodology was: define an ITSM model considering needs and constraint in small organization, map elements to ISO/IEC 20000, and validate Model in small enterprises. The ITSM Model obtained was defined using relevance base practices from ISO/IEC 20000 and considering main characteristics of small organizations. The model proposed was validated in three small companies, with positive results.