Purpose -This study seeks to identify the ideal moment for the transition from Lean Manufacturing to Industry 4.0, identifying which are the right tools for companies and industries to move towards industrialization evolution. Methodology -To analyze the maturity of Lean Manufacturing, we developed a survey based on the Lean 4.0 maturity of Matternich et. al. [1]. The questions were divided into five groups, based on the lean principles presented in Systematic Literature Review. This survey was applied to small and medium companies from Brazilian Industry. Findings -With the results in hand, it was possible to verify the relationship between the lean methodology and the technologies of Industry 4.0 and identify the best transition scenario. Originality -Many references make a theoretical analysis on the relationship between lean and Industry 4.0, while this study makes a more in-depth analysis of companies that have a certain maturity in lean and that are in the process of transition or preparing to implement Industry 4.0, with the objective of analyzing this relationship and the respective maturities and understanding some gaps presented in previous studies.Recent technologies involving cloud computing, the Internet of Things, artificial intelligence, virtual reality, and augmented reality have further revolutionized the methods and models used in current manufacturing. However, this change has not been overnight. Research and investment are necessary for our understanding of the right period in an industry's growth to make a transition into Industry 4.0.