Boman Rustom Irani established Rustomjee in Mumbai in mid-1990s, which eventually became listed company under the name Keystone Realtors in Indian stock exchanges and trades under the brand Rustomjee. Since its inception, the developer had made her first venture in Virar, that would set the tone for projects covering the entire spectrum of the housing market in Mumbai, from affordable to ultra-luxury like 9 JVPD in Juhu. In part, the nature of Rustomjee's style tends to focus on the redevelopment of slums and society lands and those such as Elita at Andheri West and the big Urbania township at Thane represent such a project, while more recent projects such as Oriana in Bandra East – undertake urban renewal in society lands.
Going green, the company has been working towards projects like Rustomjee Elements to achieve LEED certification and has accumulated good institutional partnerships over the years such as investors like HDFC Capital and IIFL. Rustomjee has kept its scope larger than just individual projects, having finished upwards of ten million square feet in residential and commercial development projects, to its community-based CSR activities related to vocational training and provision of healthcare.