Carbon nanotubes (CNTs) have been attracted huge attention over the past two decades, based on their extraordinary physical and chemical properties that are a result of their intrinsic nano-sized one-dimensional nature. Once the most promising of all nanomaterials, CNTs face stiff competition in conductive applications from graphene and other 2D materials and in mechanically enhanced composites from nanocellulose. However, after considerable research efforts, numerous multi-walled carbon nanotubes (MWNTs)-enhanced products are commercially available. Super-aligned CNT arrays, films and yarns have found applications in consumer electronics, batteries, polymer composites, aerospace, sensors, heaters, filters and biomedicine. Large-scale industrial production of single-walled carbon nanotubes (SWNTs) has been initiated, promising new market opportunities in transparent conductive films, transistors, sensors and memory devices. SWNTs are regarded as one of the most promising candidates to utilized as building blocks in next generation electronics.