Effectively applying model mix and assembly sequencing can result in smooth part usage and balanced workloads on the automotive assembly line. I have studied the problem of production planning in automotive industry in terms of scheduling various models on an assembly line using SAP APO over a time horizon. The trends in automotive industry are moving from built to stock to built to order since more customers are demanding cars specific to their requirements. This shift of interest creates a big challenge on the whole supply chain and specifically on the shop floor in automotive industry. As the number of car variants increase, the amount of products to be ordered and cars to be made specific to customer requirements creates an additional challenge on the shop floor regarding resources (Labour, Material and Equipment) optimization. The resources optimization can be done by implementing a model mix and assembly sequencing concept based on the integrated Product and Process Engineering (iPPE) structure. Using iPPE structure and takt based scheduling in SAP APO give consistent results and make the planning process simpler as the number of car variants increases though the absence of model mix percentage calculating module and lack of flexibility in editing the iPPE structure are some of the weaknesses of the system. Sequencing between departments in automotive industry using SAP APO can be investigated further.