Photo, Isabella Mejía Sierra

Isabella Mejía Sierra

Baker & McKenzie S.A.S.


Isabella is a lawyer and specialist in international business law from Universidad de los Andes. She has four years of professional experience in dispute resolution, particularly advising multinational clients in arbitration and pre-arbitration matters.

She currently serves as coordinator of the Arbitration and ADR Research Group (SAMASC) at Universidad de los Andes, and is part of the Organizing Committee of Colombia Arbitration Week.

Practice Focus

Isabella concentrates her practice in domestic and international arbitration. She has experience advising companies in the financial, mining, energy and construction sectors.

Representative Legal Matters

  • Partook in the defense of Colombia’s largest mining equipment dealer in an international arbitration valued in USD 200 million regarding disputes over maintenance and repair agreements performed between 2007 and 2020 in two coal mines.
  • Carried out the successful defense of a multinational construction engineering company, focused on renewable energies, in one of the first disputes in Colombia related to the windfarm projects in La Guajira region, a domestic arbitration valued in USD 5 million. 
  • Represented one of the top three shipping companies worldwide in an international arbitration about a joint venture agreement, achieving an award of USD 40 million in favor of the client. 
  • Advised one of Colombia’s largest energy companies in a domestic arbitration valued in USD 35 million, concerning price adjustment clauses in a share purchase agreement.
  • Aided in the defense of one of the world's largest alternative investment management companies (managing assets valued over USD 725 billion) in an international arbitration in relation to the inaccuracy of the parties’ representations and warranties in a share purchase agreement.
  • Contributed to the drafting of an amicus curiae about arrest in flagrante delicto for the Inter-American Court of Human Rights, with respect to the case of Manuela v. El Salvador, which was finally decided against the Republic of El Salvador.
  • Proposed legal arguments for memorandum for the Center for Reproductive Rights about the protocols applied in health institutions in Latin America upon the arrival of victims of sexual assault; drafted the Colombian chapter and coordinated the preparation of the Mexican and Argentinian chapters with other Baker McKenzie offices.
  • Carried out the successful defense of a health care provider institution towards 100 constitutional actions for the protection of fundamental rights (tutelas) presented against the company over the course of 1 year, obtaining a favorable decision in every case.

Professional Associations and Memberships

  • Semillero de Arbitraje y MASC de la Universidad de los Andes
  • Women in The Profession – Cyrus R. Vance Center
  • Colombian Very Young Arbitration Practitioners (COLVYAP)
  • Colombia Arbitration Week

Corporate Responsibility

  • Advised the Indian foundation CGNet Swara on the restrictions imposed by the Colombian government and Colombian law on radio licenses. 
  • Assisted in the preparation of the amicus curiae brief for the case of Manuela v. El Salvador before the Inter-American Court of Human Rights. 
  • Advised a local manufacturer of cocoa-based products in the negotiation and execution of distribution contracts.


  • Colombia (2020)


  • Universidad de los Andes (Graduate Degree in International Business Law) (2022)
  • Universidad de los Andes (Lawyer) (2020)


  • Spanish
  • English