function checkfields() {
if(document.contact.individual.value ==''){alert("Please confirm your name"); return false;}
else if (document.contact.organisation.value ==''){alert("Please confirm your organisation"); return false;}
else if (document.contact.telephone.value ==''){alert("Please confirm your telephone number"); return false;}
else if (document.contact.emailaddress.value ==''){alert("Please confirm your email address"); return false;}
return true;
}

function checkemail(){
   var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
   var address = document.contact.emailaddress.value;
   if(reg.test(address) == false) {
      alert('Invalid Email Address');
      return false;
   }
   return true;
}

function checkform(){
if (checkfields()){
if (checkemail()){
return true;
}
}
return false;
}