function Enquiry_form_check(form)  {
	if (form.ContactName.value == "") {
		alert("Please enter your Contact Name");
		form.ContactName.focus();
		return false;
	}
	if (form.TelephoneDay.value == ""  &&  form.TelephoneEvenings.value == ""  &&  form.Mobile.value == "") {
		alert("Please enter a contact telephone number");
		form.TelephoneDay.focus();
		return false;
	}
	if (form.EmailAddress.value == "") {
		alert("Please enter your Email Address");
		form.EmailAddress.focus();
		return false;
	}
	if (form.EmailAddress.value.indexOf('@',0)==-1 || form.EmailAddress.value.indexOf('.',0)==-1) {
		alert(form.EmailAddress.value + ", " + "is an invalid email address.")
		form.EmailAddress.focus();
		return false;
	}
	if (form.PreferMobile.checked == true  &&  form.Mobile.value == "") {
		alert("Please enter a mobile number or change your preferred contact method");
		form.Mobile.focus();
		return false;
	}
	if (form.PreferTelephoneDay.checked == true  &&  form.TelephoneDay.value == "") {
		alert("Please enter a daytime contact number or change your preferred contact method");
		form.TelephoneDay.focus();
		return false;
	}
	if (form.PreferTelephoneEvening.checked == true  &&  form.TelephoneEvenings.value == "") {
		alert("Please enter an evening contact number or change your preferred contact method");
		form.TelephoneEvenings.focus();
		return false;
	}
	if (form.PreferEmail.checked == true  &&  form.EmailAddress.value == "") {
		alert("Please enter an email address or change your preferred contact method");
		form.EmailAddress.focus();
		return false;
	}	
	if (form.Enquiry.value == "") {
		alert("Please enter an enquiry");
		form.Enquiry.focus();
		return false;
	}
	alert("Thanks for entering your details.");
}