diff --git a/series.py b/series.py
index adfc3ae..582251b 100644
--- a/series.py
+++ b/series.py
@@ -33,7 +33,7 @@ class SeriesSchema(ma.SQLAlchemyAutoSchema):
 class SeriesForm(FlaskForm):
     id = HiddenField()
     title = StringField('Title:', [validators.DataRequired()])
-    num_books = IntegerField('Number of Books:', [validators.NumberRange(min=1)])
+    num_books = IntegerField('Number of Books:', [validators.DataRequired(), validators.NumberRange(min=1)])
     calcd_rating = StringField('Avg Rating:' )
     note = TextAreaField('Notes:')
     submit = SubmitField('Save' )