Hi Claus, The intention with LandXML units is that one <Units> element applies to the entire file except for each <SurveyHeader> which may contain a <unit> element specific to that survey data set. So there should be only one <Units> element with either a Metric or Imperial tag set. Nathan Crews -----Original Message----- From: landxml-bounce@xxxxxxxxxxxxx [mailto:landxml-bounce@xxxxxxxxxxxxx] On Behalf Of Claus Plank Sent: Friday, February 15, 2008 8:17 AM To: landxml@xxxxxxxxxxxxx Subject: [LandXML] Choice-Tag in Schema-Files Perhaps it's a question of a newbie, but I have noticed, that there ist now restriction in the the xml-schema to have for example more than one "Units"-Tag. Is the schema wanted to work in that way? For example it is possible to get schema validness for the following Data (tested in XML-Spy): <?xml version="1.0"?> <LandXML xmlns="http://www.landxml.org/schema/LandXML-1.1"; xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; xsi:schemaLocation="http://www.landxml.org/schema/LandXML-1.1 http://www.landxml.org/schema/LandXML-1.1/LandXML-1.1.xsd"; date="2008-02-15" time="15:23:00" version="" > <Units> <Metric volumeUnit="cubicMeter" temperatureUnit="celsius" pressureUnit="milliBars" linearUnit="meter" areaUnit="squareMeter"/> </Units> <Units> <Imperial volumeUnit="acreFeet" temperatureUnit="fahrenheit" pressureUnit="inHG" linearUnit="foot" areaUnit="acre"/> </Units> <Units> <Metric volumeUnit="cubicMeter" temperatureUnit="celsius" pressureUnit="milliBars" linearUnit="meter" areaUnit="squareMeter"/> </Units> <Units> <Metric volumeUnit="cubicMeter" temperatureUnit="celsius" pressureUnit="milliBars" linearUnit="meter" areaUnit="squareMeter"/> </Units> <Units> <Metric volumeUnit="cubicMeter" temperatureUnit="celsius" pressureUnit="milliBars" linearUnit="meter" areaUnit="squareMeter"/> </Units> <CoordinateSystem><Start></Start></CoordinateSystem> </LandXML> thx in advance.