The receptionist at a well-known architectural office in Chicago answers the phone with a friendly “Nagle Hartray.” But the proper name—Nagle Hartray Danker Kagan McKay Penney Architects—rolls off the tongue like that of a corporate law firm, offering a clue to its size and ambitions. The architects, who last year had billings of $4 million, specialize in selective types of multifamily housing. For the past decade, the office roster has held steady at 27 employees. But that's about to change. More