+5  A: 

Use the corrent Panel implementation, in this case a Grid would work best:

<Grid>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="*"/>
        <ColumnDefinition Width="Auto"/>
        <ColumnDefinition Width="Auto"/>
    </Grid.ColumnDefinitions>

    <CheckBox>Details</CheckBox>
    <Button Grid.Column="1">Exit</Button>
    <Button Grid.Column="2">Reset</Button>
</Grid>

HTH, Kent

Kent Boogaart
Idd, grid is the way to go :)Come to think it, that and the canvas are ussually the only panel types I ever use :S
cwap