function validate_form ( )
{
    valid = true;

    if ( document.contact_form.contact_name.value == "" )
    {
        alert ( "Please fill in the 'Name' field"  );
        valid = false;
    }
	
    if ( document.contact_form.contact_email.value == "" )
    {
        alert ( "Please fill in the 'Email' field"  );
        valid = false;
    }	
	
    if ( document.contact_form.consultancy_name.value == "" )
    {
        alert ( "Please fill in the consultancy 'Name' field"  );
        valid = false;
    }	
	
    if ( document.contact_form.consultancy_email.value == "" )
    {
        alert ( "Please fill in the consultancy 'Email' field"  );
        valid = false;
    }		

    return valid;
}