Esper has been a member of the Houston legal community since 1998. She holds the position of Paralegal within El Paso Corporation's Corporate Secretary department. In recognition of her work in the corporate secretary's office, El Paso promoted Esperanza to the position of Senior Paralegal in 2004. In this capacity, she is responsible for all corporate governance. In addition to her career in the legal field, Esperanza worked as a transfer agent for The Coastal Corporation for 14 years..