diff --git a/examples/rmg/minimal/input.py b/examples/rmg/minimal/input.py
index 5a2effffbc..93dd6d1c26 100644
--- a/examples/rmg/minimal/input.py
+++ b/examples/rmg/minimal/input.py
@@ -4,7 +4,7 @@
     reactionLibraries = [],
     seedMechanisms = [],
     kineticsDepositories = ['training'],
-    kineticsFamilies = ['!Intra_Disproportionation','!Substitution_O'],
+    kineticsFamilies = 'default',
     kineticsEstimator = 'rate rules',
 )
 
diff --git a/rmgpy/data/kinetics/__init__.py b/rmgpy/data/kinetics/__init__.py
index 8935ff041f..77100efabd 100644
--- a/rmgpy/data/kinetics/__init__.py
+++ b/rmgpy/data/kinetics/__init__.py
@@ -41,7 +41,7 @@
 from rmgpy.molecule import Molecule, Group
 from rmgpy.species import Species
 from rmgpy.reaction import Reaction
-from rmgpy.data.base import LogicNode
+from rmgpy.data.base import LogicNode, DatabaseError
 
 from .common import KineticsError, saveEntry
 from .depository import DepositoryReaction, KineticsDepository
@@ -59,6 +59,7 @@ class KineticsDatabase(object):
     """
 
     def __init__(self):
+        self.recommendedFamilies = {}
         self.families = {}
         self.libraries = {}
         self.libraryOrder = []
@@ -101,34 +102,88 @@ def load(self, path, families=None, libraries=None, depositories=None):
         Load the kinetics database from the given `path` on disk, where `path`
         points to the top-level folder of the families database.
         """
+        self.loadRecommendedFamiliesList(os.path.join(path, 'families', 'recommended.py')),
         self.loadFamilies(os.path.join(path, 'families'), families, depositories)
         self.loadLibraries(os.path.join(path, 'libraries'), libraries)
+
+    def loadRecommendedFamiliesList(self, filepath):
+        """
+        Load the list of recommended families from the given file
         
+        The file is usually 'kinetics/families/recommended.py'.
+        This is stored as a dictionary of True or False values (checked here),
+        and should contain entries for every available family (checked in loadFamilies).
+        """
+        try:
+            global_context = {}
+            global_context['__builtins__'] = None
+            global_context['True'] = True
+            global_context['False'] = False
+            local_context = {}
+            local_context['__builtins__'] = None
+            f = open(filepath, 'r')
+            exec f in global_context, local_context
+            f.close()
+            self.recommendedFamilies = local_context['recommendedFamilies']
+        except:
+            raise DatabaseError('Error while reading list of recommended families from {0}/recommended.py.'.format(path))
+        for recommended in self.recommendedFamilies.values():
+            if not isinstance(recommended, bool):
+                raise DatabaseError("recommendedFamilies dictionary should contain only True or False values")
+
     def loadFamilies(self, path, families=None, depositories=None):
         """
         Load the kinetics families from the given `path` on disk, where `path`
         points to the top-level folder of the kinetics families.
         """
-        logging.info('Loading kinetics families from {0}'.format(path))
         
         familiesToLoad = []
         for (root, dirs, files) in os.walk(os.path.join(path)):
             if root == path:
-                if families is None or families == 'all':
-                    # All families are loaded by default
-                    for d in dirs:
+                break  # all we wanted was the list of dirs in the base path
+
+        if families == 'default':
+            logging.info('Loading default kinetics families from {0}'.format(path))
+            for d in dirs:  # load them in directory listing order, like other methods (better than a random dict order)
+                try:
+                    recommended = self.recommendedFamilies[d]
+                except KeyError:
+                    raise DatabaseError('Family {0} not found in recommendation list (probably at {1}/recommended.py)'.format(d, path))
+                if recommended:
+                    familiesToLoad.append(d)
+            for label, value in self.recommendedFamilies.iteritems():
+                if label not in dirs:
+                    raise DatabaseError('Family {0} found (in {1}/recommended.py) not found on disk.'.format(label, path))
+
+        elif families == 'all':
+            # All families are loaded
+            logging.info('Loading all of the kinetics families from {0}'.format(path))
+            for d in dirs:
+                familiesToLoad.append(d)
+        elif families == 'none':
+            logging.info('Not loading any of the kinetics families from {0}'.format(path))
+            # Don't load any of the families
+            familiesToLoad = []
+        elif isinstance(families, list):
+            logging.info('Loading the user-specified kinetics families from {0}'.format(path))
+            # If all items in the list start with !, all families will be loaded except these
+            if len(families) == 0:
+                raise DatabaseError('Kinetics families should be a non-empty list, or set to `default`, `all`, or `none`.')
+            elif all([label.startswith('!') for label in families]):
+                for d in dirs:
+                    if '!{0}'.format(d) not in families:
+                        familiesToLoad.append(d)
+            elif any([label.startswith('!') for label in families]):
+                raise DatabaseError('Families list must either all or none have prefix "!", but not a mix.')
+            else:  # only the families given will be loaded
+                for d in dirs:
+                    if d in families:
                         familiesToLoad.append(d)
-                elif isinstance(families, list) or isinstance(families, tuple):
-                    # If all items in the list start with !, all families will be loaded except these
-                    if all([label.startswith('!') for label in families]):
-                        for d in dirs:
-                            if '!{0}'.format(d) not in families:
-                                familiesToLoad.append(d)
-                    # Otherwise only the families given will be loaded
-                    else:
-                        for d in dirs:
-                            if d in families:
-                                familiesToLoad.append(d)
+                for label in families:
+                    if label not in dirs:
+                        raise DatabaseError('Family {0} not found on disk.'.format(label))
+        else:
+            raise DatabaseError('Kinetics families was not specified properly.  Should be set to `default`,`all`,`none`, or a list.')
         
         # Now we know what families to load, so let's load them
         self.families = {}
@@ -265,14 +320,15 @@ def saveOld(self, path):
 // Families can be deactivated by simply changing the "on/off" column to off.
 //
 // This file was generated by exporting the entirety of RMG-Py,
-// so has all families on by default. You may want to turn some off.
+// so the on/off decisions come from the defaults there.
 //
 ////////////////////////////////////////////////////////////////////////////////
 
 // No.  on/off  Forward reaction
 """)
             for number, label in enumerate(sorted(self.families.keys())):
-                f.write("{num:<2d}    on     {label}\n".format(num=number, label=label))
+                onoff = 'on ' if self.recommendedFamilies[label] else 'off'
+                f.write("{num:<2d}    {onoff}     {label}\n".format(num=number, label=label, onoff=onoff))
     
     def generateReactions(self, reactants, products=None, **options):
         """
diff --git a/rmgpy/data/kinetics/kineticsTest.py b/rmgpy/data/kinetics/kineticsTest.py
new file mode 100644
index 0000000000..1d7d70beb4
--- /dev/null
+++ b/rmgpy/data/kinetics/kineticsTest.py
@@ -0,0 +1,26 @@
+import os
+import unittest 
+from external.wip import work_in_progress
+
+from rmgpy import settings
+from rmgpy.data.kinetics import *
+from rmgpy.data.base import DatabaseError
+###################################################
+
+class TestKineticsDatabase(unittest.TestCase):
+    
+    def testLoadFamilies(self):
+        """
+        Test that the loadFamilies function raises the correct exceptions
+        """
+        path = os.path.join(settings['database.directory'],'kinetics','families')
+        database = KineticsDatabase()
+        
+        with self.assertRaises(DatabaseError):
+            database.loadFamilies(path, families='random')
+        with self.assertRaises(DatabaseError):
+            database.loadFamilies(path, families=['!H_Abstraction','Disproportionation'])
+        with self.assertRaises(DatabaseError):
+            database.loadFamilies(path, families=['fake_family'])
+        with self.assertRaises(DatabaseError):
+            database.loadFamilies(path, families=[])
\ No newline at end of file
diff --git a/rmgpy/rmg/input.py b/rmgpy/rmg/input.py
index 4f00636602..f3ccd43d21 100644
--- a/rmgpy/rmg/input.py
+++ b/rmgpy/rmg/input.py
@@ -82,12 +82,10 @@ def database(
     else:
         assert isinstance(kineticsDepositories,list), "kineticsDepositories should be either 'default', 'all', or a list of names eg. ['training','PrIMe']."
         rmg.kineticsDepositories = kineticsDepositories
-    if kineticsFamilies == 'default':
-        pass
-    elif kineticsFamilies == 'all':
-        pass
+    if kineticsFamilies in ('default', 'all', 'none'):
+        rmg.kineticsFamilies = kineticsFamilies
     else:
-        assert isinstance(kineticsFamilies,list), "kineticsFamilies should be either 'default', 'all', or a list of names eg. ['H_Abstraction','!Intra_Disproportionation']."
+        assert isinstance(kineticsFamilies,list), "kineticsFamilies should be either 'default', 'all', 'none', or a list of names eg. ['H_Abstraction','R_Recombination'] or ['!Intra_Disproportionation']."
         rmg.kineticsFamilies = kineticsFamilies
 
 def species(label, structure, reactive=True):