This paper presents a 3-phased Lean Construction Project (LCP) implemented in a specialized and integrated service company. The purpose of the LCP was to increase productivity and to re-structure Production Planning and Control routines. It was undertaken by a group of internal and external consultants for a period of four months of workshops and more four months of sustainability on-site. The construction project focused by the LCP was the refurbishment of a Coke Oven in a Brazilian Steel Mill. The three workshops regarding the Lean Construction background were: (a) Analysing the construction activities and support process (Planning, Contract Management, Supply, Warehouse, Safety); (b) Redesigning Production Planning and Control tools, routines and responsibilities; and defining a new Work plan schedule regarding takt-time; and (c) a Productivity Workshop implemented through wastes identification, activities reorganization and work provision. For all these workshops, a work group was formed covering consultants, managers, engineers, team-leaders and front-line workers. Finally, the workshop results were assessed through comparison of the productivity indicators with the base-line defined in the Analysis Stage. After the LCP, the project achieved its main objective with the walls assembly productivity improvement by 20%. This result was reached with fewer people performing more efficiently (less time). Moreover, the operational efficiency improvement guaranteed a 46% increase in the gross margin of the contract.