Depends on the competency. I'd venture Accenture has done half of all SAP major implementations in the world. For popular software packages, there are typically

Depends on the competency. I'd venture Accenture has done half of all SAP major implementations in the world. For popular software packages, there are typically project testimonials from dozens of other fortune 500 companies, and there is usually a "Gold-Partner" type guarantee from the software vendor themselves. When the consultancy messes up, they risk losing the Partner label or tier. https://www.sap.com/partners/find.html https://www.sap.com/partners/find.html https://pf-prod-sapit-partner-prod.cfapps.eu10.hana.ondemand.com/profile/0000828182 https://pf-prod-sapit-partner-prod.cfapps.eu10.hana.ondemand... Obviously this works for popular packages with defined success criteria, but that is a lot of business for consultancies already, and i'd argue, a great reason to go with a consultancy.