For Estimation stage projects only, the Check In/Check Out icon on the project toolbar allows estimators to lock editing for all users while the project is exported to SLIM-Estimate workbook format to use the advanced estimation and sizing features in the desktop tools. When the estimator has completed working in SLIM-Estimate, the project can be “checked in” to SLIM-Collaborate to preserve any new sizing, skills allocation, or other changes created in the desktop.