The Size and Scale Index for Exhibitions (SASIE) is the annual measurement of the scale and characteristics of the UK exhibition sector published by the Events Industry Alliance (EIA), an alliance formed by the Association of Event Organisers (AEO), the Association of Event Venues (AEV) and the Event Supplier and Services Association (ESSA). It has been running since 2014, with a break in 2020 and 2021 because of the pandemic; this ninth edition was published in April 2026. The data comes from a self-completion survey of UK venues in AEV membership and organising companies in AEO membership, collected exhibition by exhibition, reconciled to remove duplicate returns, then weighted by venue category and grossed up to an estimate for the whole sector. The report defines an exhibition as an event with at least 500m² of exhibition space and splits the market into trade exhibitions, consumer exhibitions and conferences with an exhibition element, with venues grouped as primary, secondary and other/outdoor. It covers the number and type of exhibitions, visits, duration, gross and net size, industry sectors and seasonality, and adds a 2015 to 2025 trend analysis based on a consistent sample of venues.