@raven-worx @raven-worx said: do you really insert columns? or rows? ANd do you call the signals with the correct indexes? Well the columns are properly updated with the correct information after the beginInsertColumns and endInsertColumns, so yes I am 100% certain the view is being updated when the model changes. I'm also certain that the sort and delete work as both functions are reflective in the view. yes it's not necessary to call dataChanged() with an invalid index. Rather you should call it with the index which data has cahnged obviously. I understand that, again this code was not written by me, I'm simply attempting to solve an issue that was discovered. Moving on from both of your points we still have yet to find a solution. The issue is with the selection of data, not the addition, subtracting or sorting thereof. I believe the issue had to do with the Update function (as a hunch) perhaps it is a mutex locking issue in the model?