diff --git a/catalyst/marketplace/marketplace.py b/catalyst/marketplace/marketplace.py
index 68088c5c..e972b750 100644
--- a/catalyst/marketplace/marketplace.py
+++ b/catalyst/marketplace/marketplace.py
@@ -23,7 +23,7 @@ from catalyst.exchange.utils.stats_utils import set_print_settings
 from catalyst.marketplace.marketplace_errors import (
     MarketplacePubAddressEmpty, MarketplaceDatasetNotFound,
     MarketplaceNoAddressMatch, MarketplaceHTTPRequest,
-    MarketplaceNoCSVFiles)
+    MarketplaceNoCSVFiles, MarketplaceRequiresPython3)
 from catalyst.marketplace.utils.auth_utils import get_key_secret, \
     get_signed_headers
 from catalyst.marketplace.utils.bundle_utils import merge_bundles
@@ -44,7 +44,10 @@ log = logbook.Logger('Marketplace', level=LOG_LEVEL)
 class Marketplace:
     def __init__(self):
         global Web3
-        from web3 import Web3, HTTPProvider
+        try:
+            from web3 import Web3, HTTPProvider
+        except ImportError:
+            raise MarketplaceRequiresPython3()
 
         self.addresses = get_user_pubaddr()
 
@@ -58,7 +61,7 @@ class Marketplace:
         self.web3 = Web3(HTTPProvider(ETH_REMOTE_NODE))
 
         contract_url = urllib.urlopen(MARKETPLACE_CONTRACT)
-        
+
         self.mkt_contract_address = Web3.toChecksumAddress(
             contract_url.readline().decode(
                 contract_url.info().get_content_charset()).strip())
@@ -72,7 +75,7 @@ class Marketplace:
         )
 
         contract_url = urllib.urlopen(ENIGMA_CONTRACT)
-  
+
         self.eng_contract_address = Web3.toChecksumAddress(
             contract_url.readline().decode(
                 contract_url.info().get_content_charset()).strip())
@@ -150,13 +153,13 @@ class Marketplace:
               'Gas Price:\t\t[Accept the default value]\n'
               'Nonce:\t\t\t{nonce}\n'
               'Data:\t\t\t{data}\n'.format(
-            _from=from_address,
-            to=tx['to'],
-            value=tx['value'],
-            gas=tx['gas'],
-            nonce=tx['nonce'],
-            data=tx['data'], )
-        )
+                _from=from_address,
+                to=tx['to'],
+                value=tx['value'],
+                gas=tx['gas'],
+                nonce=tx['nonce'],
+                data=tx['data'], )
+              )
 
         signed_tx = input('Copy and Paste the "Signed Transaction" '
                           'field here:\n')
@@ -261,14 +264,14 @@ class Marketplace:
                   'buy: {} ENG. Get enough ENG to cover the costs of the '
                   'monthly\nsubscription for what you are trying to buy, '
                   'and try again.'.format(
-                address, from_grains(balance), price))
+                    address, from_grains(balance), price))
             return
 
         while True:
             agree_pay = input('Please confirm that you agree to pay {} ENG '
                               'for a monthly subscription to the dataset "{}" '
                               'starting today. [default: Y] '.format(
-                price, dataset)) or 'y'
+                                price, dataset)) or 'y'
             if agree_pay.lower() not in ('y', 'n'):
                 print("Please answer Y or N.")
             else:
@@ -371,7 +374,7 @@ class Marketplace:
               'You can now ingest this dataset anytime during the '
               'next month by running the following command:\n'
               'catalyst marketplace ingest --dataset={}'.format(
-            dataset, address, dataset))
+                dataset, address, dataset))
 
     def process_temp_bundle(self, ds_name, path):
         """
@@ -428,10 +431,10 @@ class Marketplace:
             print('Your subscription to dataset "{}" expired on {} UTC.'
                   'Please renew your subscription by running:\n'
                   'catalyst marketplace subscribe --dataset={}'.format(
-                ds_name,
-                pd.to_datetime(check_sub[4], unit='s', utc=True),
-                ds_name)
-            )
+                    ds_name,
+                    pd.to_datetime(check_sub[4], unit='s', utc=True),
+                    ds_name)
+                  )
 
         if 'key' in self.addresses[address_i]:
             key = self.addresses[address_i]['key']
diff --git a/catalyst/marketplace/marketplace_errors.py b/catalyst/marketplace/marketplace_errors.py
index b6be1c3b..488c204f 100644
--- a/catalyst/marketplace/marketplace_errors.py
+++ b/catalyst/marketplace/marketplace_errors.py
@@ -9,7 +9,8 @@ def silent_except_hook(exctype, excvalue, exctraceback):
                    MarketplaceNoAddressMatch, MarketplaceHTTPRequest,
                    MarketplaceNoCSVFiles, MarketplaceContractDataNoMatch,
                    MarketplaceSubscriptionExpired, MarketplaceJSONError,
-                   MarketplaceWalletNotSupported, MarketplaceEmptySignature]:
+                   MarketplaceWalletNotSupported, MarketplaceEmptySignature,
+                   MarketplaceRequiresPython3]:
         fn = traceback.extract_tb(exctraceback)[-1][0]
         ln = traceback.extract_tb(exctraceback)[-1][1]
         print("Error traceback: {1} (line {2})\n"
@@ -86,3 +87,11 @@ class MarketplaceJSONError(ZiplineError):
         'The configuration file {file} is malformed. Please correct '
         'the following error:\n{error}'
     )
+
+
+class MarketplaceRequiresPython3(ZiplineError):
+    msg = (
+        '\nCatalyst requires Python3 to access the Enigma Data Marketplace.\n'
+        'If you want to use the Data Marketplace, you need to reinstall '
+        'Catalyst\nwith Python3. See the documentation website for additional '
+        'information.')
diff --git a/etc/python2.7-environment.yml b/etc/python2.7-environment.yml
index b2e2486c..3835d7d4 100644
--- a/etc/python2.7-environment.yml
+++ b/etc/python2.7-environment.yml
@@ -23,7 +23,9 @@ dependencies:
   - bottleneck==1.2.1
   - chardet==3.0.4
   - ccxt==1.10.1094
-  - web3==4.0.0b7
+# The Enigma Data Marketplace requires Python3 because it depends on
+# web3, which requires Python3, as building its dependencies breaks in Python2
+#  - web3==4.0.0b7
   - requests-toolbelt==0.8.0
   - click==6.7
   - contextlib2==0.5.5
diff --git a/etc/requirements.txt b/etc/requirements.txt
index 73573e45..5be47e3d 100644
--- a/etc/requirements.txt
+++ b/etc/requirements.txt
@@ -84,5 +84,5 @@ tables==3.3.0
 ccxt==1.10.1094
 boto3==1.4.8
 redo==1.6
-web3==4.0.0b11
+web3==4.0.0b11; python_version > '3.4'
 requests-toolbelt==0.8.0
diff --git a/etc/requirements_marketplace.txt b/etc/requirements_marketplace.txt
deleted file mode 100644
index 2a56c200..00000000
--- a/etc/requirements_marketplace.txt
+++ /dev/null
@@ -1,2 +0,0 @@
-web3==4.0.0b7
-requests-toolbelt==0.8.0