## 6 Conclusions  
The major strengths of LIBS from the application point of view are the versatility, the multi-element detection, and the field suitability of the method. LIBS enables for fast measurements without or with only little sample preparation reaching detection limits in the low ppm range, typically. The major limitation of LIBS is its rather low sensitivity (\"ppm barrier\"), which does not compete with laboratory-based laser analytical techniques such as LA-ICP-MS and LA-ICP-OES. These methods have better analytical performance in terms of LOD and LOQ reaching values in the ppb range, typically. However, the field suitability of LIBS enables to use LIBS-based sensors for in-line and at-line measurements in industrial production and for other applications under harsh conditions out of the laboratory. The ongoing rapid development of laser sources, efficient spectrometers, and sensitive light detection systems is a driving force for the further development of robust LIBS systems and of hand-held LIBS devices. New solid state lasers with high repetition rate and high average power, e.g., advanced fiber lasers and compact Nd:YAG lasers, are supporting this development. Fast element analysis of primary and secondary raw materials, of semi-finished workpieces, and of finished goods is an area with large growth potential. LIBS-based sensors can contribute to the efficient use of resource materials and the accurate chemical monitoring of materials in production. The progress in LIBS measurement technology and the increasing demands for efficient production processes will continue triggering the development of new in-line, at-line, and on-site applications of this laser-analytical method in the near future. Conceptualization, J.D.P. ; methodology, J.D.P. ; validation, S.T., S.G., N.G., S.E.-F. and J.H. ; investigation, S.T., S.G., N.G., S.E.-F. and J.H. ; withring--original draft preparation, J.D.P. ; writing--review and editing, J.D.P. ; funding acquisition, J.D.P. All authors have read and agreed to the published version of the manuscript. This research was funded by the Austrian Research Promotion Agency FFG (K-Project Photonic Sensing for Smarter Processes (PSSP, project No 871974), Project CAPCOAT Plus (project  
Figure 23: In-situ LIBS measurement of tungsten inert gas (TIG) stainless steel welding. (**a**) Experimental set-up of welding and LIBS equipment. (**b**) Intensities of Cr I/Fe I (black squares), Ni I/Fe I (red circles), and Mn I/Fe I (blue triangles) were measured at different distance to the welding arc (HAZ is heated affected zone). Adapted from [402]. No 872846)). Further funding was provided by the Competence Center CHASE GmbH, which is funded by the Austrian Research Promotion Agency FFG (project No 868615) within the COMET (Competence Centers for Excellent Technologies) program by BMVIT, BMDW, and the Federal Provinces of Upper Austria and Vienna. **Institutional Review Board Statement:** Not applicable. **Informed Consent Statement:** Not applicable. **Data Availability Statement:** The datasets analyzed or generated during the study are not publicly archived. All datasets are compiled from data available in the cited references. **Acknowledgments:** We appreciate the close cooperation with our industrial partners: VOESTALPINE Stahl GmbH with [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON]; LENZING AG with [PERSON], [PERSON], [PERSON]; KRAIBURG Austria GmbH & Co KG with [PERSON], [PERSON]; AVE Osterreich GmbH with [PERSON], [PERSON], [PERSON]; FRONIUS International GmbH with [PERSON], [PERSON]; and TEUFELBERGER GmbH with [PERSON], [PERSON]. Many thanks go to [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], and all further group members for the intense scientific cooperation. **Conflicts of Interest:** The authors declare no conflict of interest.