Book excerpt: A comprehensive look at Volvo’s innovative, 21st century double-decker designs and how they transformed busing across London. Volvo’s successful B7TL low-floor double-decker bus enjoyed a successful six-year run until increasing noise problems in London curtailed demand. The company then developed a leaner and quieter update which it dubbed the B9TL, and orders resumed in strength. As diesel-engine buses gradually gave way to battery-hybrid technology in the late 2000s, Volvo unveiled the B5LH hybrid to immediate acclaim and even healthier London sales. Volvo’s B9TLs and B5LHs quickly became the standard double decker buses in operation across London. This book offers a comprehensive account of these important and innovative machines.