The fashion industry is the second most polluting industry in the world, mostly due to the many ways fashion is polluting the environment (Fischer, 2015). First of all by the CO2 emission produced in manufacturing and logistics, second the massive amounts of water used in dyeing processes and production of natural resources, third the pollution of groundwater and rivers by pesticides and dyes and last but not least the enormous amount of waste created by fast fashion items that are only worn once. One of the most impactful garments in this industry is something most of us wear every day: a pair of jeans. The production of a single pair uses on average 8000 litres of water (Water Footprint Network, 2016). Besides water, toxic and corrosive chemicals are used to dye and ‘wash’ the jeans to its desired style. Every year, more than 2 billion pairs of jeans are produced worldwide, adding to its yet existing footprint (Greenpeace, 2016). Some brands in the industry are already putting a lot of effort into the production of sustainable denim. However, reducing the impact of the denim industry is not just up to denim brands and manufacturers anymore: consumers have to play their part as well. To raise awareness and higher the demand for sustainable jeans amongst consumers, this graduation project for House of Denim focusses on solving the following challenge: how might we help consumers buy better jeans? To raise the demand for sustainable jeans, the impact of a jeans has to become more transparent and understandable for consumers. In an attempt to achieve this, a jungle of certifications has popped up in the fashion and jeans industry, resulting in more confusion than transparency; many consumers are not familiar with any of these existing certifications. Besides awareness, understanding what a certification stands for demands quite some knowledge of materials or manufacturing from consumers. To make it easier for consumers to make a positive choice, Brighter Blue, a product rating tool, was developed in cooperation with denim experts and consumers. To accomplish this, the project used an inside- out approach to research the impact of a pair of jeans, to see what factors contribute most to this impact and to explore how this impact could be minimised. Afterwards, a case study was used as a parallel perspective, to see and learn how indices in other industries help change behaviour. Qualitative interviews with eight denim experts and a literature study on green consumer behaviour defined the most important challenges and design guidelines for Brighter Blue. These guidelines were further developed into a first minimum lovable prototype of the rating: the impact index. From this moment and outside-in approached was used to develop this concept using lean methodology. Through three design interventions with important industry stakeholders and (expert) consumers, the rating was developed into the final concept Brighter Blue. Brighter Blue is a positive and easy indicator of the best jeans out there: accessible on various levels to serve as many consumers as possible. By means of a hangtag and Google extension, the ratings are communicated to consumers, so they can look good and feel confident that they have made the right choice. An overarching platform conveys the message that sustainable choices do not have to be that hard or complicated: everyone can vote with their money. Brighter Blue helps consumers regain their power to decide and gives a little push to young conscious consumers that want to make better choices but not always know how. This thesis presents the development and final concept of Brighter Blue, including the rating methodology, working mechanism, benchmarks, prototypes of the various consumer tools, and a detailed plan for further implementation and market launch.