A Field is an offshore field located at offshore of Peninsular Malaysia, facilitated with an integrated oil and gas processing plant, water injection facilities and gas lift infrastructure. The field was brought to oil production in end of 2001 and achieved the peak production of about 120 Mbopd in 2005. In early of 2002, it started gas production at an initial rate of about 300 MMscf/d which is currently maintained at about 300–350 MMscf/d. The crude oil production peak was followed by a moderate decline over the next three years. Besides crude oil and gas production, the field also produces condensate as by product while producing gas. It was recognized that a proactive field management strategy was required in order to minimize any further production decline as the field production forecast showed a declining trend. Since A Field is one of major gas contributors, its gas production sustainability is very important to fulfill the gas demand in the region. The current gas sources in A Field are natural gas reservoir as the main source and the associated gas from oil production. It was recognized that subsurface and surface integrity is the key success for sustaining A Field gas production. The integration is important to ensure proper planning and execution for gas development within the A Field area as well as sustaining the crude oil production. There are several alternatives to maintain gas production. The analysis presented here describes the use of an integrated approach involving multi-disciplines to achieve the most suitable decision and maximize value creation focusing on A gas sustainability.