The drainage area maximization problem for an unconventional hydrocarbon field is addressed with the objective of designing a development plan that optimizes total production while satisfying environmental and operating constraints. The various characteristics of the problem are presented and a solution approach is developed around an integer linear programming model applied to a discretisation of the field’s geographical area. Computational experiments show that the approach provides a practical response to the problem, generating solutions that comply with all of the constraints. The algorithm implemented under this approach has been incorporated into a software tool for planning and managing unconventional hydrocarbon operations and has been used since 2018 by two leading petroleum companies in Argentina to improve unconventional development plans for the country’s “Vaca Muerta” geological formation.