Our Team
Joshua Mandelbaum I Executive Director
Joshua is committed to using his decades of nonprofit experience to strengthen and grow the work of St. George’s Society of New York.
As Executive Director of Words without Borders, an organization dedicated to advancing cross-cultural understanding through the promotion of international literature, he turned a volunteer-run literary magazine into an international destination for literature in translation with a burgeoning education program. As Executive Director of 826NYC, youth writing organization, he helped a Brooklyn youth writing nonprofit double its capacity and expand to all five boroughs of New York City.
In his free time, he is working toward a master’s degree in psychoanalysis, and lives with his wife and son in Brooklyn.
Jessica Sims | Development & Membership Manager
Jessica leads on SGSNY’s programmatic and fundraising initiatives. She is also the point of contact for our members and volunteers. She holds a PhD in Continental Philosophy from Stony Brook University and brings more than 10 years of academic teaching and administrative experience to the team. While her esoteric knowledge of European thinkers isn’t always appreciated in the real world, it sure does come in handy at networking events and pub quizzes.
Jessica received a $20,000 scholarship from the American Association of University Women (AAUW) in 2016 for her contributions to female scholarship in the US. She lives in Queens with her husband and spends her free time practicing yoga and meditation in Astoria.
Alex Dalrymple | Senior Events & Communications Manager
Alex oversees communications and events for SGSNY. After spending nearly a decade working with female entrepreneurs, non-profit organizations, and government agencies whose missions she strongly stands behind, Alex is thrilled to be working with such an impressive team at SGSNY devoted to critical causes.
Having launched her communications career with the NYC Department of Education, the largest school district in the nation with 1.1 million students, she became well-versed in the power of using captivating storytelling to engage the incredibly diverse families of New York City. After seven years at the NYC DOE, she worked as a freelance communications consultant where she has been working with various clients committed to education and/ or equity.
Outside of the office, Alex is a foodie and theater enthusiast, heading to nearby Broadway for a show from her leafy suburb in New Jersey whenever she can. An avid international traveler, her favorite adventure of all has been the search for the best playground the NYC metro area has to offer with her young daughter, Charlie, and husband, Joe.
Julie Rosenberg LMSW |Manton Social Worker
Julie has served as a social worker for St. George’s Society of New York since 2012, providing counseling, help with benefits and advocacy for our senior beneficiaries so they can afford to stay safely in their homes.
Prior to this, she worked with seniors facing eviction in housing court and ran an elder abuse program at the District Attorney’s office in Queens. She lives in Brooklyn with her two kids and rescue dog, El Chapo.
Patrick Mell | Program & Membership Coordinator
Patrick completed his studies at University College Dublin, where he achieved a degree in Politics, International Relations, and Economics. He has moved to New York from Dublin, Ireland as part of a year long placement with the Mountbatten Program, a program designed to help young people develop their skills, opportunities, and networks while allowing them to experience life in a new setting.
Patrick has served as a Scout Leader for the past five years, organizing and leading events, and successfully planning international camps for young people aged 12-17. In 2017 Patrick spent time in Ghana, where he taught English to schoolchildren. This experience inspired his career in the non-profit sector.
Leah Jones | Communications & Events Coordinator
Leah graduated with a degree in Digital Media from the University of Leeds, where she built a strong foundation in digital design, web development, and visual communication. Originally from Belfast, she now lives in New York as part of the Mountbatten Program, a year-long international placement focused on professional and cultural exchange.
Leah has experience in communications and event management across higher education and health research. At the University of Leeds, she created digital content and coordinated student events to boost engagement. Most recently, at the National Institute for Health and Care Research (NIHR), Leah supported dementia research campaigns and worked with UK charities on outreach projects engaging underrepresented communities.
Outside of work, Leah enjoys capturing New York’s lively atmosphere through photography and trying every bagel spot in Brooklyn—when she’s not getting lost on the subway, of course!
Marie Marais | Program Coordinator
Bringing a wealth of global corporate wisdom to St. George's, Marie is passionate about supporting the Beneficiary Program. In her part-time role, she's revolutionizing operations by streamlining and automating processes, always with an eye toward making things easier for the end-user—a skill perfected during her corporate career.
When not at St. George's, Marie divides her time between consulting, nurturing the next generation of leaders through coaching, and helping others find their physical and mental strength as a Pilates instructor.