This book examines various unique applications and their effectiveness of constructed wetlands for the treatment of complex and heavily polluted wastewater from industrial sources. It also highlights the technological and advanced knowledge in application of constructed wetlands through different microbiological and advanced biochemical technologies. Special attention is paid to suspended solids, organic matter, and nutrient removal. Deep insights are provided for facilities such as those in oil and gas industries, agro-industry, paper and pharmaceutical manufacturing, the textile industry, wineries, breweries, and sludge treatment, among others. Constructed wetlands are low-cost and sustainable systems for wastewater treatment. Traditionally, they have been used for urban and domestic wastewater treatment, but in the last two decades, applications for industrial wastewater treatment have increased due to the advances of the technology and extended research in the field. The advances have also been encouraged by the economic, environmental, and societal advantages over conventional technologies. This book helps academicians and industrialists obtain detailed knowledge about constructed wetlands in the field of wastewater treatment.