Abstract: The invention relates to an additive manufacturing system 10 for manufacturing a product 300 layer-by-layer. The system 10 includes a production arrangement 12 which is configured to manufacture a product 300 layer-by-layer upon receiving instructions from a control arrangement 32. The control arrangement 32 is operatively connected to the production arrangement 12 and is configured to control the operation of the production arrangement 12 by providing control instructions for each layer of a product 300 to be manufactured to the production arrangement 12. The system 10 includes an optical monitoring arrangement 14 which is configured to capture an image of a layer manufactured by the production arrangement and/or a layer of source material laid/placed over a previously manufactured layer of the product 300. The optical monitoring arrangement 14 is also configured to send the captured image to the control arrangement for processing.