Due to the discovery of "Camisea" gas field in Peru in the mid-1980s and its private investment promotion at the beginning of 2000, natural gas has gained a key role in Peru's energy matrix. The Peruvian gas industry -a fledgling one in that period- was forced to devise financial mechanisms in order to get its development. One of them, perhaps the most important, was the creation of the "Main Transportation and Distribution Pipelines Guarantee" (GRP, as its acronym in Spanish). GRP is a financial tool to ensure the annual income of investors in the transportation and distribution of natural gas. This is an additional payment made by energy customers for the shortfall that might exist between an expected income and an income that is guaranteed by the transportation and distribution of natural gas concession contracts, to adequately reward the cost of service of the concessionaires. GRP reduces the investment risk of transportation and distribution gas service and makes it possible the development of the gas industry. It would not have been possible to install Peruvian main transportation and distribution pipelines such as "Camisea" project if GRP had not been created. Even if "Camisea" had been concluded, the price of gas transportation service would have been high and the costs of power plants (pipeline main customers) would have increased, with a consequent impact on electricity prices and the failure of gas industry. GRP is all a Peruvian regulatory conception. It will make possible future projects that will provide energy access to the poorest regions in the country. Based on its key role played in Peru, the proposed paper will expose how the GRP works, the agents who are required to pay it and, as a conclusion, why it is so important for the economic development and energy access.