Marie-Claire Gladstone (nee Claessen) moved to Manhattan in 2006 after living in Monaco for ten years. From Monte Carlo, she initially worked throughout the South of France as a real estate agent and salesperson and later founded her own company which engaged in public relations and event planning, catering to real estate and luxury lifestyle companies in the Cote d'Azur.

Marie-Claire was born in The Netherlands and grew up in Amsterdam until she attended the Le Rosey School in Switzerland. She later attended the Anderson school of Business at UCLA where she studied marketing and received an MBA.

Following graduation, Marie-Claire returned to Europe to follow a career in business. Being thoroughly fluent in Dutch, German, English, Italian and French, helped to facilitate this transition. Prior to locating to Monaco she lived in Florence, Milan and Paris, when she was employed in the fashion industry. During that time she used her skills in marketing and language and achieved positions at Salvatore Ferragamo, John Galliano and Donna Karan.

Being extremely well-travelled, Marie-Claire has contacts and enjoys friendships throughout the world: Europe, the Middle East, the Americas, Asia, Africa and Australia. Her international friends and business relationships are engaged in diverse fields and pursuits ranging from fashion, music, hospitality and sports to finance, manufacturing and industry. Her ability to genuinely maintain these relationships is a rare talent and reveals her sincerity and character. She expresses an ease with people and is, therefore, well-suited to facilitate interactions with many diverse and demanding individuals. She is also highly motivated, conscientious and understands the importance of team effort.

Marie-Claire has supported charities such as Yele Haiti, while in Monaco and The Princess Grace Foundation, in New York. She is married and is an avid skier.