Nowadays, when most businesses are moving forward to sustainability by providing or getting different services from different vendors, Service Level Agreement (SLA) becomes very important for both the business providers/vendors and for users/customers. There are many ways to inform users/customers about various services with the inherent execution functionalities and even nonfunctional/ Quality of Service (QoS) aspects through SLAs. However, these basic SLA actually did not cover eco-efficient green issues or IT ethics issues for sustainability. That is why Green SLA (GSLA) should come into play. Green SLA is a formal agreement incorporating all the traditional commitments as well as green issues and ethics issues in IT business sectors. GSLA research would survey on different basic SLA parameters for various services such as network, compute, storage and multimedia in IT business areas. At the same time, this survey would focus on finding the gaps and incorporation of these basic SLA parameters with existing green issues for all these mentioned services. Finally, this research would also focus on the integration of green parameters in existing SLAs, defining GSLA with new green performance indicators and their measurable units. This proposed GSLA could help and clarify different service providers/vendors to design their future business strategy in this new transitional, sustainable society.