arcgis desktop - Retaining all fishnet grid squares within boundary of polygon from another feature class?

I have created a fishnet grid (3km x 3km) over a vector polygon.

I now want to clip the fishnet over the vector polygon retaining all grid squares within the boundary of the polygon.

Therefore I want all squares that would typically be clipped into partial squares to remain as whole squares.

Does anybody know how to do this?

Answer

You are mixing a lot of terminology which is making your question rather confusing. You talk about "clipping" but then state "within the boundary" and finally you say you want all whole squares, that's 3 different things!

I'm assuming that you want all squares that are intersecting the polygon, which would include all whole squares completely within the polygon and whole squares touching the boundary of the polygon. Therefore, what you want is to use the Select By Location tool with the relationship of Intersects.

This will select those squares which you then export to a new dataset.