diff --git a/acme_nginx/AcmeV1.py b/acme_nginx/AcmeV1.py
index fb47951..187bc3e 100644
--- a/acme_nginx/AcmeV1.py
+++ b/acme_nginx/AcmeV1.py
@@ -7,7 +7,7 @@
     from urllib.request import urlopen  # Python 3
 except ImportError:
     from urllib2 import urlopen  # Python 2
-from Acme import Acme
+from .Acme import Acme
 
 
 class AcmeV1(Acme):
diff --git a/acme_nginx/AcmeV2.py b/acme_nginx/AcmeV2.py
index 9dda97a..28c60f9 100644
--- a/acme_nginx/AcmeV2.py
+++ b/acme_nginx/AcmeV2.py
@@ -6,8 +6,8 @@
     from urllib.request import urlopen, Request  # Python 3
 except ImportError:
     from urllib2 import urlopen, Request  # Python 2
-from Acme import Acme
-from DigitalOcean import DigitalOcean
+from .Acme import Acme
+from .DigitalOcean import DigitalOcean
 
 
 class AcmeV2(Acme):
diff --git a/acme_nginx/client.py b/acme_nginx/client.py
index 6137f25..867eba6 100644
--- a/acme_nginx/client.py
+++ b/acme_nginx/client.py
@@ -1,5 +1,7 @@
 import argparse
 import logging
+from .AcmeV1 import AcmeV1
+from .AcmeV2 import AcmeV2
 
 
 def set_arguments():
@@ -75,13 +77,13 @@ def main():
     logging.basicConfig(format='%(asctime)s - %(levelname)s - %(message)s', level=log_level)
     log = logging.getLogger('acme')
     if args.acmev1:
-        from AcmeV1 import AcmeV1 as Acme
+        Acme = AcmeV1
         if args.staging:
             api_url = 'https://acme-staging.api.letsencrypt.org'
         else:
             api_url = 'https://acme-v01.api.letsencrypt.org'
     else:
-        from AcmeV2 import AcmeV2 as Acme
+        Acme = AcmeV2
         if args.staging:
             api_url = 'https://acme-staging-v02.api.letsencrypt.org/directory'
         else: