The STACK / QuickBooks Online integration turns a process taking hours into a process measured in milli-seconds. No more cutting and pasting countless rows of data from STACK into QuickBooks. No more errors during data entry. Additionally, unlike some competing approaches, the STACK method does not impose a new workflow or mapping table. It allows users to maintain their current structure and established processes, resulting in accurate invoices and purchase orders sent out on time and with minimal effort.