Nuno Prospero dos Santos

You can use many different free tools (such as Zonum Solutions or ArcScripts) to convert from Keyhole Markup Language (KML) to ESRI Shapefile (SHP) and vice-versa.

The best advice I can give you is keeping on thing in mind: Google Earth only reads and writes KML/KMZ using the WGS 1984 coordinate system. That means that:

• If you are converting SHP to KML, you should convert your shapefile to WGS1984. Use the “Project” tool in ArcToolbox and select that coordinate system. You must define the projection function in order to work… Then, use the above tools to convert to KML. Simple.
• In case you are converting KML to SHP, do the following: open the ArcMap with a blank document. Add any kind of shapefile in your own coordinate system (Datum, UTM, etc). The mxd will gain that coord system. Convert the KML to SHP using the tools I’ve mentioned before. Add the output shapefile to the mxd and ArcMap will convert it to your coordinate system. If you want it permanently in that format, use the Project tool in ArcToolbox. Remember to fill in the projection function.

Success? Troubles? If you have any doubts related to this matter, contact me.