PLS was started in 1987 to adapt the real estate industry's highly effective MLS (multiple listing service) for the oil and gas industry. The firm takes its name from the simple concept of a "Petroleum Listing Service" but PLS has since expanded to provide buyers and sellers the information, marketing and advisory services they need to better manage their portfolios and facilitate profitable transactions. To that end, PLS publishes various listing, news and research reports; offers various data and information tools; brokers and direct markets properties, prospects, overrides and midstream assets for sellers seeking additional services; and provides advisory and consulting services on an as needed or project basis.

The firm performs several hundred consulting studies each year for a variety of clients and has earned worldwide recognition for reliably predicting the performance of complex oil and gas reservoirs in all major petroleum provinces. Through exceptional petroleum engineers and geoscientists, client services include reserves evaluations, geoscience/geology studies, field development and EOR design, reservoir simulation, economic analysis, management consulting and expert witness testimony. Since 1998, Ryder Scott has been the most widely used consulting firm for preparing annual petroleum reserves certifications for filers with the U.S. Securities & Exchange Commission and has proudly served clients listed on the Ontario, Toronto, London, Hong Kong, Australia and other stock exchanges.