Sensors are perhaps the most important and integral components of our modern societies. With the ever-increasing emphasis on global warming and environmental pollution, optimized performance of current and future energy systems and process industries is of the highest importance. Accurate sensing and quantification of the key parameters of such systems is vital to monitoring, control and optimization efforts. Laser-based in-situ optical sensors are best suited to provide the desired characteristics of being accurate, sensitive, selective, portable, fast, safe and smart. Significant progress has been made over the last decade or so in the development and deployment of laser-based sensing solutions, though new challenges and opportunities continue to emerge at a rapid pace. This paper focuses on sensors based on laser absorption spectroscopy (LAS) due to their simple architecture, ease of implementation and field deployment. Recent years have witnessed strong emphasis on the mid-IR wavelength region (fingerprint region) of the electromagnetic spectrum due to the presence of strong fundamental vibrational bands of many species of interest, availability of laser systems and the opportunities to do sensitive as well as selective detection. This paper will briefly describe some of the recent mid-IR sensing works being done in the author’s research group.