>Suppose I have a grid that's running off of a table. The grid displays 4 fields across from this table. When the third field is TRUE for particular line, I want this line of the grid to be disabled. How do I do this?

Only the ActiveRow or all diplayed rows with the third field TRUE?

Take a look at the Grid's DynamicCurrentControl property. It could be used to do what you want. It does cost some performance - The expression is evaluated for every row showing in the grid everytime the grid refreshs.

Bill