Microfluidics is a highly interdisciplinary field covering the areas of biology, chemistry and engineering. Microfluidic systems manipulate, control, and study the behaviour of fluids within a network of micro-channels, making it an attractive technology for both academia and industry. The main advantages of microfluidics over the traditional methods involve 1) extremely low volume of reagents (up to pLno more than 1 pL), 2) faster analysis, 3) portability, 4) less waste generation, and 5) precisely controlled environments. Furthermore, the integration of multiple processes into single devices has allowed for automation and simplicity of use, even by non-experts. Miniaturizing biochemical and chemical techniques has gained increased attention in the last few years, due to the low costs and sensitivity. The objective of this collection is to highlight the development of microfluidic devices with integrated biochemical or chemical techniques for applications in medicine, drug analysis, forensics and environmental sciences. These novel microfluidic devices integrate single and multiple techniques depending on the desired application. A few non-exhaustive examples involve 1) platforms for disease detection, such as the identification and quantification of pathogens, 2) mimicry of drug metabolism using liver on a chip and microfluidic electrochemical cells, 3) integrated microfluidics for forensic DNA analysis, combining the essential steps of DNA extraction and DNA amplification, and 4) microfluidic systems for extraction, separation or detection of environmental contaminants.