Defne specializes in corporate, real estate, litigation, and dispute resolution.

She advises international institutions, national governments, international companies, Turkish corporates, and start-ups for issues relating to corporate governance, compliance, anti-corruption, employment, and regulatory law. She represents both buyers and sellers in connection with the acquisition of a variety of assets and businesses. She also advises clients regarding local and cross-border disputes involving administrative, tax, customs, employment, business crime, and commercial and collection issues.

Before joining Cetinkaya as a founding partner, Defne worked in private practice as a senior lawyer with another leading Turkish law firm. She was in-house counsel for a Turkish corporate and has represented a non-governmental organization.