SciEsp is a tool for scientific writing i Spanish. Its objective is to help students whe writing abstracts of scientific texts, such as a thesi or a dissertation. The tool identifies the differen components of an abstract structure according t the guidelines of "good writing" proposed by th literature. Each sentence in the abstract is classifie to one of six different rhetorical categories (background gap, purpose, methodology, result, or conclusion) warning the writer of a possible missing componen of the "optimal" structure. We manually annotated corpus of abstracts from computer science theses an dissertations, and use it to train a Naive Bayes classifie that achieves an F1-measure of 0.65. We expect tha SciEsp becomes a starting point for further projects i the area of supporting technologies for scientific writin in Spanish.