This paper addresses the concept of Sustainability 4.0 in services, which can be defined as an integrated approach that seeks to balance the dimensions of the triple bottom line (economic, social, and environmental factors) using Industry 4.0, enabling technologies to improve organizational processes. This paper aims to identify the contextual relationships between the sustainable solutions of I4.0 based on the principles and pillars of Industry 4.0 in services while using Interpretive Structural Modeling (ISM). The ISM model, composed of 16 sustainable solutions, was developed based on the vision of a law firm manager and validated by 19 experts. As a result, the model presented a six-level hierarchy for sustainable solutions and classified sustainable solutions for law firms as Dependent Sustainable Solutions, Liaison Sustainable Solutions, and Independent Sustainable Solutions. Moreover, this study highlights the importance of sustainable solutions in Industry 4.0 in services, raising awareness of the need for sustainable practices in organizations. Therefore, this research contributes to the advancement of scientific knowledge, offers practical guidance for law firm managers, and promotes sustainability in Industry 4.0 in services, benefiting both academia and society.