Here is an example on how I was able to add an XY event layer to an MXD (using arcpy for ArcGIS 10):import arcpy
from arcpy import env
from arcpy import mapping
env.workspace = r"C:\TEMP\Python\test.gdb"
env.overwriteOutput = 1
table = "XY"
#Make XY event layer
arcpy.MakeXYEventLayer_management(table, "X", "Y", "XY_event")
#Save XY event to a layer file
arcpy.SaveToLayerFile_management("XY_event", r"C:\temp\Python\XY_event.lyr")
#Add layer file to MXD
mxd = mapping.MapDocument(r"C:\temp\python\Airports.mxd")
for df in mapping.ListDataFrames(mxd):
lyr = mapping.Layer(r"C:\temp\python\XY_event.lyr")
mapping.AddLayer(df, lyr)
arcpy.RefreshTOC()
arcpy.RefreshActiveView()
mxd.save()
del lyr, mxd, df