PLP Architecture has officially launched construction on the first tower of Tokyo Cross Park, a flagship project that serves as the new global headquarters of Japan’s tech giant NTT. Unveiled in 2022 as a large-scale urban regeneration initiative within the Tokyo metropolitan area, the masterplan took a significant step forward on December 5, 2025, with the groundbreaking of its inaugural phase.
Project Overview & Key Partners
The NTT Hibiya Building, designed by PLP Architecture, is a collaborative development between NTT Urban Development and Tokyo Electric Power Company. Rising 230 meters tall with a total floor area of 361,000 square meters, it stands as the centerpiece of the 1.1 million-square-meter Tokyo Cross Park vision. Beyond designing the tower itself, PLP Architecture oversees the overall masterplanning and placemaking strategy for the broader development, redefining the role of corporate headquarters within urban landscapes.
Nestled in Tokyo’s city center, the project spans a 6.5-hectare site and includes approximately 150,000 square meters of office space. It is engineered to support distributed work models, enabling cross-location collaboration through shared digital environments rather than relying solely on in-person interactions. The building’s systems are designed to adapt to occupancy levels and usage demands, with adjustable lighting, climate control, and flexible spatial layouts that cater to evolving work and activity patterns.
Digital Infrastructure Integration
A core feature of the NTT Hibiya Building is its integration with NTT’s pioneering digital infrastructure initiative, IOWN (Innovative Optical and Wireless Network). This next-generation communication network leverages optical technology to enable high-capacity data transmission while minimizing latency and energy consumption. By replacing certain electronic processes with optical alternatives, IOWN aims to enhance data capacity, reduce delays, and cut energy use compared to traditional networks. Within the building, this infrastructure supports adaptive building systems and a digitally responsive environment, fostering seamless connectivity and operational efficiency.
Public Spaces & Collaborative Hubs
At ground level, the three-story “Cross Gate” serves as a public interface between the tower and the city. This versatile space is designed to host a wide range of events and daily activities, with interior surfaces that accommodate visual displays. Floors 7 to 10 house an innovation hub, bringing together enterprises, researchers, and institutional partners from urban development, information and communication technology, and energy sectors to drive cross-industry collaboration.
The 9th floor will feature a 400-seat cultural hall, designed to host live events with views of Hibiya Park. In a nod to sustainability and heritage, the hall incorporates recycled materials from NTT’s former building that previously occupied the site. It is also equipped to support live connections with venues across Japan, expanding its cultural and collaborative reach.
Sustainability & Environmental Commitments
Environmental goals guide every aspect of the project, from building performance to material selection. The office areas are on track to meet “ZEB Ready” (Zero Energy Building Ready) standards, targeting a more than 50% reduction in energy consumption compared to conventional office buildings. The construction utilizes sustainable materials such as recycled aluminum, low-carbon concrete, and electric arc furnace steel.
Additionally, the design explores the integration of emerging building management technologies with low-emission energy sources, including hydrogen. These measures underscore the project’s commitment to minimizing environmental impact while setting new benchmarks for sustainable urban development in Tokyo.
As Tokyo Cross Park takes shape, the NTT Hibiya Building is poised to become more than a corporate headquarters—it will serve as a dynamic urban landmark that blends digital innovation, public engagement, and environmental stewardship. With PLP Architecture’s vision and NTT’s technological expertise, the project is set to redefine modern urban living and working in one of the world’s most vibrant metropolises.
