Most of the approaches to improve software process focus on formal process descriptions based on models and standards of best practices. However, the human factor has not been covered, as a result, an important gap arises between processes description and process execution. This gap takes special value in Small and Medium Enterprises (SMEs) because most of them do not have enough resources (time, budget and human) to implement a software process improvement (SPI) without a guarantee of any result due to the investment it represents for them. In order to help SMEs in the implementation of SPI initiatives, this paper presents a set of identified needs that SMEs must face in the implementation of SPI since the human perspective. Moreover, the needs are compared with the results of a local study perform at SMEs of Zacatecas. Besides, the paper includes a proposal focusing on two factors which aims to help them covering the set of needs. Finally, the paper shows the relation of these two factors and the SPI manifesto. © Springer-Verlag Berlin Heidelberg 2014.