function checkData() {
	if (document.form.firstname.value==""){
		alert ("Please enter your first name")
		document.form.firstname.focus();
		return false;
	}
	if (document.form.lastname.value==""){
		alert ("Please enter your surname")
		document.form.lastname.focus();
		return false;
	}
	if (document.form.company.value==""){
		alert ("Please enter the name of your company/business")
		document.form.company.focus();
		return false;
	}
	if (document.form.jobtitle.value==""){
		alert ("Please enter your job title or position")
		document.form.jobtitle.focus();
		return false;
	}
	if (document.form.address1.value==""){
		alert ("Please enter your full address")
		document.form.address1.focus();
		return false;
	}
	if (document.form.town.value==""){
		alert ("Please enter your full address")
		document.form.town.focus();
		return false;
	}
	if (document.form.county.value==""){
		alert ("Please enter your full address")
		document.form.county.focus();
		return false;
	}
	if (document.form.postcode.value==""){
		alert ("Please enter your postcode")
		document.form.postcode.focus();
		return false;
	}
	if (document.form.telephone.value==""){
		alert ("Please enter your daytime contact number")
		document.form.telephone.focus();
		return false;
	}
	if (document.form.email.value==""){
		alert ("Please enter your email address")
		document.form.email.focus();
		return false;
	}
	if (!document.getElementById("groupbuyer").checked && !document.getElementById("hotelbuyer").checked && !document.getElementById("guesthousebuyer").checked && !document.getElementById("bandbbuyer").checked && !document.getElementById("selfcatbuyer").checked && !document.getElementById("other").checked) {
		alert ("Please choose your type of enquiry");	
		document.getElementById("groupbuyer").focus();
		return false;
	}
	if (!document.getElementById("tuesday").checked && !document.getElementById("wednesday").checked) {
		alert ("Please choose the day you wish to attend");	
		document.getElementById("tuesday").focus();
		return false;
	}
	if (document.form.marketing.value==""){
		alert ("Please tell us how you heard about the show")
		document.form.marketing.focus();
		return false;
	}
	return true;
}