Principals

Ms. Leheny joined Phillips Preiss in March 2005, rose to become a principal in 2011, and is now serving the firm as Managing Principal. Her work focuses primarily on public sector clients with an emphasis on master planning, affordable housing planning and compliance (including providing expert planning testimony in Superior Court), drafting of land use ordinances, redevelopment studies and plans, Highlands Council compliance, historic preservation, design guidelines, and development application review. Among her current clients are the Boroughs of Morris Plains, Netcong, Mountain Lakes, and Harrington Park; as well as the Townships of Long Hill, Cranbury, and Morris. She provides planning services to a number of other municipalities throughout New Jersey, as well as the Fort Monmouth Economic Redevelopment Authority (FMERA). Recent work includes drafting the Township of Bloomfield Master Plan, which was the recipient of an Achievement in Planning Award from the New Jersey Planning Officials. Ms. Leheny prepared land use standards for the redevelopment of the former Fort Monmouth in Monmouth County to a state of the art motion picture production studio for Netflix, as well as Fourth Round affordable housing plans and compliance ordinances for numerous municipalities. Ms. Leheny holds an M.S. in Historic Preservation from Columbia University and a Master of City Planning from the Massachusetts Institute of Technology.

Mr. Grygiel joined the firm in 2000 and became a principal in 2002. He specializes in comprehensive and neighborhood planning, development review and zoning analysis. Mr. Grygiel is an experienced expert witness who has appeared before planning and zoning boards in over 150 municipalities throughout New Jersey, as well as in Superior Court. He also regularly presents at planning conferences and seminars, and is a member of the New Jersey Planning Officials' Board of Planning Advisors.

Mr. Grygiel integrates economic development, transportation and market considerations into his land use planning projects in order to help create actionable plans. He directed the preparation of the City of Hoboken Master Plan, which won the New Jersey Chapter of the American Planning Association (APA-NJ) Outstanding Comprehensive Plan Award. His recent projects include preparation of a master plan update for North Bergen, New Jersey, zoning amendments for New Milford, New Jersey and Roslyn, New York, and redevelopment studies and plans for New Jersey municipalities including Maplewood, Bloomfield, and Seaside Heights. He also is the consulting planner for multiple municipalities and has reviewed complex development applications on behalf of land use boards in municipalities throughout New Jersey and Long Island. Mr. Grygiel received a Master of Regional Planning degree from the University of North Carolina at Chapel Hill and a Bachelor of Arts in Urban Studies from Rutgers University in New Brunswick, New Jersey.

Ms. Keller joined Phillips Preiss as a planner in 2012 and became a principal in 2020. She has demonstrated expertise in providing a range of land use planning and development advisory services to both the public and private sectors, including drafting zoning ordinances and regulatory updates, preparing redevelopment plans and studies, reviewing municipal development applications, and conducting real estate and feasibility analyses. Ms. Keller has been a member of project teams involved in award-winning local and regional planning efforts as supported by the North Jersey Transportation Planning Authority and Somerset County Planning Board. On the private side, Ms. Keller works with a range of clients to obtain approvals that reflect their visions, including on behalf of Princeton University’s innovative mixed-use proposal for the Princeton Nurseries site in Plainsboro, and Lincoln Equities in their reuse of a former pharmaceutical campus in Hopewell Township as a biotechnology hub. She also regularly serves private development clients as an expert witness before planning and zoning boards across the state.

Ms. Keller holds a Master of City Planning degree from the University of Pennsylvania, from where she also earned a Bachelor of Arts in Urban Studies.

Ms. Trahan is a community planning consultant who is driven to achieve the best planning outcomes for the communities she serves. She joined Phillips Preiss as a Senior Planner in 2019 and rose to become an associate principal of the firm in 2025. Ms. Trahan supports municipal clients with a range of services, including development review for land use boards, preparation of redevelopment studies and plans, affordable housing planning and compliance, facilitation of public forums and visioning workshops, and development of forward-looking master plans and reexamination reports. For private clients, Ms. Trahan reliably provides expert planning testimony before land use boards to gain approval of residential, commercial, and large-scale development applications.

Prior to joining Phillips Preiss, Ms. Trahan worked throughout the tri-state area on land use planning, environmental analysis, transportation planning, grant writing, and community and economic development. Ms. Trahan received a Master of City and Regional Planning degree from the Bloustein School at Rutgers University in New Brunswick, New Jersey, and holds a Bachelor of Arts degree from the University of Richmond.

Mr. Phillips joined the firm in 1977 and served as its managing principal until 2025. In addition to his land use planning and master plan work, Mr. Phillips directed the firm’s real estate, Redevelopment, and condemnation-related assignments. For over 30 years, he provided expert planning services to various municipal boards and governing bodies; educational institutions; major real estate developers; and corporations looking to relocate and/or expand facilities in New Jersey. He obtained approvals for hundreds of private development projects throughout the State. Mr. Phillips’ work received awards from the NJ Chapter of the American Planning Association, New Jersey Future, New Jersey Planning Officials, and Downtown New Jersey. In 2021, the New Jersey Chapter of the American Planning Association awarded the Budd Chavooshian Award for Outstanding Professional Planner to Mr. Phillips in honor of his distinguished career. Mr. Phillips continues to provide high-level expert planning consulting services to select clients on an as-need basis.

Mr. Preiss joined the firm in 1981 and served as a partner from 1984 until his retirement in 2021. In his 40 year career at the firm, Mr. Preiss became a highly regarded expert in the field of land use planning working for both public and private sector clients.  In 2012 the New Jersey Planning Officials recognized Mr. Preiss’ contribution to the planning profession by awarding him the Achievement in Planning Award.  He also found time to co-author the Illustrated Book of Development Definitions (4th edition), which is the authoritative resource on planning and zoning terms for planning, development, and design professionals.