Micro and nano technologies have already contributed significantly to technological advances in a number of industries, including the electronics, biomedical, pharmaceutical, materials and manufacturing, aerospace, photography, and more recently the energy industries. Micro and nano technologies have the potential to introduce revolutionary changes in several areas of the oil and gas industry, such as exploration, drilling, production, enhanced oil recovery, refining and distribution. For example, nanosensors might provide more detailed and accurate information about reservoirs; specially fabricated nanoparticles can be used for scale inhibition; structural nanomaterials could enable the development of petroleum industry equipment that is much lighter and more reliable and long-lasting; and nanomembranes could enhance the gas separation and removal of impurities from oil and gas streams. Other emerging applications of micro and nano technologies in the petroleum industry are new types of "smart fluids" for enhanced oil recovery (EOR) and drilling. In short, there are numerous areas in which nanotechnology can contribute to more efficient, less expensive, and more environmentally sound technologies. This paper provides an overview of the micro and nano technologies with a particular focus on nanotech-based solutions for the oil and gas and the broader energy industry. Recent developments in research in areas of significance to the oil and gas industry are briefly reviewed and include two case study examples. The potential opportunities and challenges that face future trends of nanotechnology applications in the oil and gas industry are also discussed.