The 5th Spectral Lineshapes in Plasmas (SLSP) Workshop will be held in Vrdnik, Serbia, 27 – 31 May 2019 is organized in cooperation with the International Atomic Energy Agency (IAEA). The Workshop series facilitates the comparison of different computational and analytical methods for the calculation and analysis of line shapes for diagnosis purposes in laboratory and space plasmas. By detailed comparison of results for a selected set of case problems, it becomes possible to pinpoint sources of disagreements, infer limits of applicability, and assess accuracy.