[en] This document is the guide to understanding the second pillar of the NZI dashboard, also referred to as pillar B. Pillar B is aimed at quantifying a firm's positive impact on the greenhouse gas emissions of its ecosystem. It is composed of two major families: B2: how the company's solutions contribute to decarbonization, B3: the company's financial contribution to projects to reduce emissions outside its value chain. For the first family, this guide offers: 1) A general methodological framework for calculating and reporting avoided emissions generated by corporate solutions; 2) A toolbox containing: Detailed methodologies for calculating avoided emissions for three economic sectors: Mobility, Construction and Energy; Quantified applications for certain solutions in France: Avoidance Factors (FEv) to quickly estimate avoided emissions. Conceptual framework: avoided emissions are the difference between emissions in a reference situation and emissions in a situation with a decarbonizing solution. The emissions in these two situations depend on the context in which the solution is implemented: geography, client profiles, market segments, etc. - Choice of reference situation: two main types of reference situations have been identified; - the previous situation and the average of the market context. Net Zero Initiative describes a typology of contexts that enables the identification of a robust reference situation for a given context. - Timeframe: Avoided emissions are calculated for the entire lifespan of the solution sold by the company. It is possible to update the calculation annually by using the input data corresponding to the year of calculation. - Perimeter: The calculation of avoided emissions is done according to a life-cycle rationale: emissions from production, utilization, end of life, etc. have to be taken into account. - Evolution of emissions though time: The projected decarbonization of energy and other dynamic effects must be taken into account in the calculations. - Precision level of hypotheses: the calculation of avoided emissions may have varying levels of precision: specific to each solution sold, company average, or market average. The level of precision depends particularly on the type of solution and the availability of data. Covered in the present report: Mobility, Construction and Energy. The toolbox provides sector-specific methodological sheets on avoided emissions for each solution/context pair. For certain solutions, it also provides detailed methodological sheets and the first generation of Avoidance Factors (AFv) in France. The guide proposes a method for reporting additional avoided emissions generated by financing projects outside the company's value chain