Documentation describing the data sets of two surveys conducted with the aim of identifying and validating critical success factors (CSFs) in the implementation of Lean Six Sigma (LSS) in manufacturing SMEs in Colombia is included. The first, at a general level and named E1, had the objective of identifying manufacturing SMEs in Colombia that have implemented Lean, Six Sigma or LSS. The second, of a specific level and named E2, was applied in the SMEs found in E1 and had the objective of identifying and prioritizing the CSFs in the implementation of LSS and to assess their importance and practice using Likert-type scales. It also made it possible to identify the best-known and most used LSS tools and investigate the specific results of LSS implementation in SMEs. The questionnaire proposed by J. Antony et al. (2008) and adapted by Timans et al. (2012) for LSS was used. The consent to use is included in the documentation. The technical concept of four LSS experts in Colombia was requested to adapt expressions to the context. In the statistical validation phase of the identified CSFs, the estimation of a set of statistical criteria commonly used in psychometric research was made using statistical software SPSS® Version 26 from IBM®. The validation of the factorial structure of the complete model made up of the identified factors and their observable variables was done through a Confirmatory Factorial Analysis using the graphic software SPSS Amos® Version 26 also from IBM®. To build the graphic model the observable variables (statements in the questionnaire E2 of Section III) were represented by rectangles and identified with the letter P (question in Spanish) and with the number according to the order of appearance from 1 to 51 (Example, P1). The critical success factors (CSFs), which are the variables that are not directly measurable or latent, were represented with ovals and identified with the letter F for factor and with the number according to the order of appearance in the questionnaire E2 Section III from 1 through 13 (Example, F1) The following documentary support files are included: Dataset documentation.pdf file Consent for the use of the E2 questionnaire.pdf file Anonymized data from E1 survey with 352 complete responses in the E1_survey_dataset.exc file. Anonymized data from E2 survey with 44 complete responses in the E2_survey_dataset.exc file. E1 survey instrument with all survey items in the E1_survey_instrument.pdf file. E2 survey instrument with all survey items in the E2_survey_instrument.pdf file. Factorial structure of the CSFs of the initial model in the CFA_CSF Amos file. CSFs SPSS file.