Sidara

Sidara is a privately owned international consulting and professional-services group whose principal historical identity was associated with Dar Al-Handasah, also known as Dar Group. The organization works across engineering, architecture, urban and regional planning, environmental consulting, project and construction management, facilities management, and economics. Its work is generally delivered through a portfolio of specialist firms and brands rather than through a single consumer-facing product line. The company was founded in November 1956 in Lebanon by Kamal Al-Shair, Nazih Taleb, and three other engineering professors from the American University of Beirut. The Arabic name Dar Al-Handasah translates approximately as “the house of engineering,” reflecting the organization’s original professional-services orientation. From its Lebanese base, the group developed an international presence and became involved in major transport, infrastructure, urban-development, building, and public-sector projects. Expansion has included both organic development and acquisitions. In 1986, the group acquired the United States design practice Perkins&Will, broadening its architectural and design capabilities. In 1989, it acquired the United States-based engineering consultancy T. Y. Lin International, adding further expertise in transportation and structural engineering. The group later acquired the United Kingdom-based engineering and advisory firm Currie & Brown in 2012. These transactions helped create a multi-disciplinary platform spanning design, engineering, project advisory, cost and commercial management, and related built-environment services. Projects associated with the group include the Prai River Bridge in Penang, Malaysia; the Jamaraat Bridge and Haramain High Speed Railway in Saudi Arabia; Abraj Al-Bait Towers in Mecca; Lusail Sports Arena and Katara Towers in Qatar; Al Bayt Stadium in Qatar; and the Iconic Tower in Egypt’s New Administrative Capital. The portfolio illustrates the company’s concentration on complex infrastructure and large-scale developments, including transport systems, bridges, stadiums, towers, and major urban projects. In 2006, the organization received the Institution of Structural Engineers’ Award for Transportation Structures and its Supreme Award for the Prai River Bridge. In December 2023, the group changed its name to Sidara, replacing the Dar Group and Shair and Partners identity at the group level while Dar Al-Handasah remained one of the group’s associated companies. The new identity presents the organization as a broader international platform encompassing firms such as Currie & Brown, Dar Al-Handasah, Introba, Perkins&Will, Penspen, and T. Y. Lin International. According to the supplied reference material, Sidara acquired Aberdeen-based engineering firm John Wood Group in November 2025. Because the supplied material does not provide ownership, revenue, executive, or headquarters details, those fields are left unspecified here.

Sidara traces its origins to November 1956, when Kamal Al-Shair, Nazih Taleb, and three other professors from the American University of Beirut Engineering School established an engineering consultancy in Lebanon. The firm was given the Arabic name Dar Al-Handasah, meaning approximately “the house of engineering.” Its founding structure connected the company to academic engineering expertise and established a professional-services model centered on technical advice, design, and project delivery rather than manufacturing or consumer products. Over time, the organization developed from a Lebanese engineering practice into an international consultancy group. Its activities expanded beyond conventional engineering to include architecture, planning, environmental services, project and construction management, facilities management, and economics. This multidisciplinary scope allowed the group to participate in projects requiring coordinated architectural, structural, transportation, environmental, commercial, and program-management expertise. The group’s international expansion included important acquisitions in the United States. In 1986, it acquired Perkins&Will, a design and architecture firm. In 1989, it acquired T. Y. Lin International, a consultancy known for engineering work, particularly in transportation and structures. These transactions widened the group’s geographic reach and increased its ability to combine architecture with infrastructure and structural engineering. A further expansion step came in 2012, when the group acquired Currie & Brown, a United Kingdom-based engineering and advisory consultancy. Currie & Brown strengthened capabilities connected with cost management, project advisory, commercial management, and the delivery of complex capital projects. The broader group subsequently operated through a collection of specialist companies and affiliations, including Dar Al-Handasah, Currie & Brown, Introba, Perkins&Will, Penspen, and T. Y. Lin International. The group has been associated with a wide range of large-scale projects. The Prai River Bridge in Penang, completed in 2005, was recognized in 2006 by the Institution of Structural Engineers with awards for transportation structures and its Supreme Award. Other selected projects include the Jamaraat Bridge in Saudi Arabia, completed in 2007; Abraj Al-Bait Towers in Mecca, completed in 2012; Lusail Sports Arena in Qatar, completed in 2014; the Haramain High Speed Railway in Saudi Arabia, completed in 2018; Katara Towers in Lusail, completed in 2020; Al Bayt Stadium in Al Khor, completed in 2021; and the Iconic Tower in Egypt’s New Administrative Capital, completed in 2024. In December 2023, the organization adopted Sidara as its group-level name. The rebranding marked a transition from the better-known Dar Group identity to a name intended to represent the group’s wider collection of international professional-services businesses. Dar Al-Handasah remained among the group’s principal associated companies. The supplied reference material further records an acquisition of Aberdeen-based engineering firm John Wood Group in November 2025. Detailed information about the transaction’s terms, ownership structure, executive leadership, and financial consequences is not provided in the available material.

1. 2025John Wood Group acquisition

   The supplied reference material records Sidara’s acquisition of Aberdeen-based engineering firm John Wood Group in November.

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2. 2023The group adopts the Sidara name

   Dar Group changes its group-level name to Sidara in December.

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3. 2012Currie & Brown joins the group

   The group acquires the United Kingdom-based engineering consultancy Currie & Brown.

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4. 2006Prai River Bridge receives structural-engineering awards

   The bridge receives the Institution of Structural Engineers Award for Transportation Structures and the Supreme Award.

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5. 2005Prai River Bridge is completed

   The group completes the Prai River Bridge in Penang, Malaysia.

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6. 1989Acquisition of T. Y. Lin International

   The group acquires the United States-based consultancy T. Y. Lin International, strengthening its engineering and transportation expertise.

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7. 1986Acquisition of Perkins&Will

   The group acquires the United States-based design firm Perkins&Will, expanding its architecture and design capabilities.

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8. 1956Dar Al-Handasah is founded in Lebanon

   Kamal Al-Shair, Nazih Taleb, and three other American University of Beirut engineering professors establish the consultancy in November.

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An international, privately held multidisciplinary consultancy serving complex infrastructure, architecture, engineering, planning, and built-environment projects.

• Engineering consultingProfessional services

  Sidara’s engineering work covers the planning and design of complex infrastructure and buildings. Its associated companies provide specialist capabilities in structural, transportation, civil, and other engineering disciplines, supporting projects from early feasibility and concept development through detailed design and delivery.

• Architecture and designArchitecture and design services1986

  Through Dar Al-Handasah and associated design practices including Perkins&Will, the group provides architectural, interior, urban-design, and multidisciplinary design services. These capabilities have been applied to major towers, sports venues, transport facilities, and urban-development projects.

• Infrastructure and transportation planningInfrastructure consulting

  The group advises on transportation and infrastructure programs, including bridges, rail systems, roads, and related public works. Its project portfolio includes the Prai River Bridge, the Jamaraat Bridge, and the Haramain High Speed Railway.

• Project and construction managementProject advisory

  Sidara’s professional-services platform includes project and construction management, facilities management, cost management, and commercial advisory. These services help clients coordinate design, procurement, construction, budgets, schedules, and operational requirements on large capital projects.

• Environmental and economic consultingAdvisory services

  The group also operates in environmental consulting and economics. These disciplines support planning, impact assessment, development strategy, investment appraisal, and public- or private-sector decision-making associated with infrastructure and urban projects.

• 2025Acquire John Wood GroupM&A

  The supplied reference material describes a further expansion of Sidara’s international engineering platform.

  What changed. Sidara acquired Aberdeen-based engineering firm John Wood Group in November 2025.

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• 2023Rebrand the group as SidaraStrategy

  The organization had expanded beyond the historical Dar Al-Handasah identity into a portfolio of international consulting and design businesses.

  What changed. In December, the group changed its name from Dar Group to Sidara.

  Aftermath. Sidara became the group-level identity while Dar Al-Handasah and other specialist companies continued as associated businesses.

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• 2012Acquire Currie & BrownM&A

  The group pursued additional capabilities in engineering, project advisory, cost management, and commercial services.

  What changed. It acquired the United Kingdom-based engineering consultancy Currie & Brown.

  Aftermath. Currie & Brown became part of the group’s international network of specialist professional-services firms.

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• 1989Acquire T. Y. Lin InternationalM&A

  The group continued international expansion into specialist engineering and transportation consulting.

  What changed. It acquired United States-based consultancy T. Y. Lin International.

  Aftermath. The transaction broadened the group’s engineering and transportation capabilities.

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• 1986Acquire Perkins&WillM&A

  The group sought to expand its international design and architecture capabilities.

  What changed. It acquired the United States-based design firm Perkins&Will.

  Aftermath. The acquisition added a significant architecture and design platform to the group’s engineering-oriented activities.

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• 2025Sidara acquires John Wood Group

  According to the supplied reference material, Sidara acquired the Aberdeen-based engineering firm John Wood Group in November 2025.

  M&A
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• 2023Dar Group adopts the Sidara name

  The international consulting group changed its group-level name from Dar Group, also associated with the Shair and Partners identity, to Sidara.

  OtherLeadership change
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• 2006Prai River Bridge receives major structural-engineering awards

  The group received the Institution of Structural Engineers Award for Transportation Structures and its Supreme Award for the Prai River Bridge in Penang, Malaysia.

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1. Sidara (company)
2. Official Sidara group website