Corporate Sustainability is today a key issue for companies considering value generation, climate change and social requirements. This sustainability must be achieved in the economic, social, and environmental aspects; many authors have studied the variables that make up these aspects. Despite the importance of employees in Corporate Sustainability, to our knowledge, no studies have connected the variables with the impact that employees have on them. Therefore, in this study, combining a literature review with a Panel Delphi with 11 experts, we seek consensus on: 1) the relevance of the different variables that define Corporate Sustainability; 2) on which variables can employees have an impact; and 3) what employee behaviors are more susceptible of having this impact. The results show consensus on employees and propose behaviors that could enhance some of the most important variables of economic, social and environmental sustainability. This result opens up the possibility of developing a scale to measure employee sustainable behaviors and to understand how companies can facilitate these behaviors.