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Abstract: The mass difference between isotopes of the same element generates slight variations of the properties of their electronic cloud. This physical fact makes it possible to separate one isotope from the others by bringing an appropriate amount of coherent light energy to its constituent atoms or molecules. This laser material interaction is carried out in the three major known laser processes: atomic vapour laser isotope separation (AVLIS), molecular laser isotope separation (MLIS), and selection of isotopes by laser excitation (SILEX).Part of the required energy must be delivered in a selective manner to bring the selected isotope to an appropriate level of excitation. Since the laser and optics technologies are currently being developed in a very fast and efficient manner worldwide larger and larger varieties of laser lights are therefore available. As a result the range of possible spectroscopic options to be used as efficient photo-excitation sequences becomes wider and wider. The technological options to generate the gas material stream are mainly constrained by the throughput of an installation which changes a lot depending on the targeted production: large amounts of low enriched uranium (LEU) production or lower amounts at higher enrichment levels. From a safeguards point of view, the Additional Protocol provides strong tools to monitor activities in this domain. In particular tracking R&D activities can be done by complementary access based on the thorough review of all available information. However, there are serious obstacles to identifying any undeclared activities in this field such as the obsolescence of the section of Annex II of the AP addressing laser technologies, the development of more compact laser light sources allowing the reduction of the size of integrated installations, the possibility of using depleted uranium (DU) for such activities and increased research on laser isotopic separation of stable isotopes. Last but not least, there is no physical hurdle to apply these three processes to actinides other than uranium