Sierra Infosys is an SAP consulting firm that provides SAP upgrade services using a proprietary tool-based approach. They have experience performing upgrades for various large, global companies across multiple industries. Their services include assessing clients' systems, planning and executing upgrades, minimizing downtime, and helping clients take advantage of new functionality. They have successfully upgraded clients from versions such as 4.6B, 4.7, and 4.0B to ECC 5.0.