diff --git a/erpnext/crm/doctype/lead/lead.py b/erpnext/crm/doctype/lead/lead.py
index 605b9e9..18c0db4 100644
--- a/erpnext/crm/doctype/lead/lead.py
+++ b/erpnext/crm/doctype/lead/lead.py
@@ -4,7 +4,7 @@
 from __future__ import unicode_literals
 import frappe
 from frappe import _
-from frappe.utils import cstr, validate_email_add, cint, comma_and, has_gravatar
+from frappe.utils import cstr, validate_email_add, cint, comma_and, has_gravatar, nowdate
 from frappe.model.mapper import get_mapped_doc
 
 from erpnext.controllers.selling_controller import SellingController
@@ -38,11 +38,16 @@
 				validate_email_add(self.email_id, True)
 
 			if self.email_id == self.lead_owner:
-				# Lead Owner cannot be same as the Lead
-				self.lead_owner = None
+				frappe.throw(_("Lead Owner cannot be same as the Lead"))
+
+			if self.email_id == self.contact_by:
+				frappe.throw(_("Next Contact By cannot be same as the Lead Email id"))
 
 			self.image = has_gravatar(self.email_id)
 
+		if self.contact_date and self.contact_date < nowdate():
+			frappe.throw(_("Next Contact Date cannot be in the past"))
+
 	def on_update(self):
 		self.add_calendar_event()