XY data coordinate system projection errors

[AmyCottrell]

When I add XY (lat,long) data to the map in the same PCS and GCS as the other layers, the points are added to the map but do not line up with the other layers. I am using GCS: GCS_North_American_1983, and PCS: NAD_1983_UTM_Zone_16N. When I change the XY data to WGS_1984, the points appear on the other layers. However, I am unable to run any measuring tool. I am trying to use the Near tool to measure distance between the XY data and a polygon layer. This does not work, probably because they are in different coordinate systems. I've also tried converted the XY data into a shapefile and that doesn't work either.

Any suggestions are greatly appreciated. 

[JoeBorgione]

Here is what I would do: decide what projection you want to perform your analysis in.  My guess is since you already have the polygons in some system, you'll probably use it.  Add your xy data with the method that gets aligned correctly and then save that event layer as a feature class in the same projection of your polygons.