This multi-phased/multi-year improvements project on an occupied research laboratory facility required extensive communication and exacting safety standards to ensure the safety of occupants of the building, as well as to pedestrians and traffic in the area. The project encompassed the entire exterior of the former Necco Building at 250 Massachusetts Avenue in Cambridge and consisted of the installation of new exterior structural steel under the existing windows, installation of masonry lintels, flashings, AVB, repairs to the concrete structure behind the masonry skin and complete removal and rebuilding of the parapets and roof perimeter.