The Alfa Romeo 156, a compact executive car produced from 1997 to 2007, represents a distinctive blend of sporty handling, engaging driving dynamics, and elegant Italian styling. Built on the Tipo 3 platform and manufactured in Pomigliano d'Arco, Italy, this D-segment vehicle was designed to compete with established luxury brands, offering a range of Twin Spark petrol and JTD diesel engines, alongside manual, automatic, and Selespeed transmissions. Available as both a saloon and a sportwagon, the 156 was recognized for its characteristic design philosophy, emphasizing driver engagement and a refined yet athletic presence, earning it a shortlist for European Car of the Year in 1998. This comprehensive workshop service and repair manual provides extensive guidance for the Alfa Romeo 156 across its production years. It covers all major vehicle systems, including engine mechanicals, fuel, ignition, cooling, lubrication, exhaust, and management systems, as well as drivetrain, suspension, steering, braking, and electrical components. Detailed procedures for maintenance, troubleshooting, and repair are included, alongside technical specifications, component diagrams, and information on special tools. This manual is an indispensable resource for owners, mechanics, and technicians seeking to maintain, diagnose, and repair the Alfa Romeo 156, ensuring its optimal performance and longevity.