A Working Instruction (WI) is a verbal or written instruction or briefing of how to make a certain work or job. WIs serve as a guideline or manual for the staff and the quality of their work. The different steps of the work are often visualized in a flowchart or as a checklist. WIs can be effective catalysts to drive performance improvement and improving organizational results. Every good quality system is based on its SOPs which have to be defined in the Quality Manual and WIs which additionally specify certain internal processes.