Natural dyes are known for their use in colouring of food substrate, leather as well as natural fibres like wool, silk and cotton. These produce very uncommon, soothing and soft shades as compared to synthetic dyes. On the other hand, synthetic dyes, though available at economical prices, have many adverse effects including the threat towards the natural ecosystem. Hence, there has been an increased interest towards use of textiles (preferably natural fibre product) dyed with eco-friendly natural dyes. However, appropriate dyeing techniques/procedures are important to obtain newer shades with acceptable colour fastness behaviour and reproducible colour yield. Relevant scientific studies on standardization of dyeing methods, dyeing process variables, dyeing kinetics and test of compatibility of selective natural dyes have become very important. The present book describes the fastness and other characteristics of natural dyes obtained from five different tree barks, namely Jackfruit (Atrocarpus heterophyllus), Mahua (Madhuca indica), Neem (Azadirachta indica), Peepal (Ficus regillous) and Sal (Shorea robusta).