diff --git a/pyvckit/did.py b/pyvckit/did.py
index 6bab487..dedea78 100644
--- a/pyvckit/did.py
+++ b/pyvckit/did.py
@@ -10,7 +10,7 @@ from jwcrypto import jwk
 from urllib.parse import urlparse
 from nacl.signing import SigningKey
 from nacl.encoding import RawEncoder
-from templates import did_document_tmpl
+from pyvckit.templates import did_document_tmpl
 
 
 def key_to_did(public_key_bytes, url):
diff --git a/pyvckit/sign_vc.py b/pyvckit/sign_vc.py
index 1ff9cb2..80ed292 100644
--- a/pyvckit/sign_vc.py
+++ b/pyvckit/sign_vc.py
@@ -1,9 +1,9 @@
 import json
 import argparse
-from utils import now
-from did import generate_did, get_signing_key, key_read
-from templates import credential_tmpl, proof_tmpl
-from sign import sign_proof
+from pyvckit.utils import now
+from pyvckit.did import generate_did, get_signing_key, key_read
+from pyvckit.templates import credential_tmpl, proof_tmpl
+from pyvckit.sign import sign_proof
 
 
 # source: https://github.com/mmlab-aueb/PyEd25519Signature2018/blob/master/signer.py
diff --git a/pyvckit/sign_vp.py b/pyvckit/sign_vp.py
index 5f6ba8d..3dc9589 100644
--- a/pyvckit/sign_vp.py
+++ b/pyvckit/sign_vp.py
@@ -1,10 +1,10 @@
 import json
 import argparse
 
-from utils import now
-from templates import presentation_tmpl, proof_tmpl
-from did import key_read, generate_did, get_signing_key
-from sign import sign_proof
+from pyvckit.utils import now
+from pyvckit.templates import presentation_tmpl, proof_tmpl
+from pyvckit.did import key_read, generate_did, get_signing_key
+from pyvckit.sign import sign_proof
 
 
 def sign_vp(signing_key, holder_did, vc):
diff --git a/pyvckit/verify.py b/pyvckit/verify.py
index b4f2cbe..eee4c54 100644
--- a/pyvckit/verify.py
+++ b/pyvckit/verify.py
@@ -6,7 +6,7 @@ import multiformats
 
 from nacl.signing import VerifyKey
 
-from sign import to_jws_payload
+from pyvckit.sign import to_jws_payload
 
 
 def get_signing_input(payload):
diff --git a/pyvckit/verify_vc.py b/pyvckit/verify_vc.py
index 50a1eb0..3f30539 100644
--- a/pyvckit/verify_vc.py
+++ b/pyvckit/verify_vc.py
@@ -1,5 +1,5 @@
 import argparse
-from verify import verify_vc
+from pyvckit.verify import verify_vc
 
 
 def get_credential(path_credential):
diff --git a/pyvckit/verify_vp.py b/pyvckit/verify_vp.py
index ab2011f..fce1ca6 100644
--- a/pyvckit/verify_vp.py
+++ b/pyvckit/verify_vp.py
@@ -1,6 +1,6 @@
 import json
 import argparse
-from verify import verify_vc
+from pyvckit.verify import verify_vc
 
 
 def get_presentation(path_presentation):
diff --git a/tests/test_certificate.py b/tests/test_certificate.py
index eaff672..ec2901d 100644
--- a/tests/test_certificate.py
+++ b/tests/test_certificate.py
@@ -3,12 +3,12 @@ import multicodec
 import multiformats
 import nacl.encoding
 
-from did import generate_keys, generate_did, get_signing_key, gen_did_document
-from sign_vc import sign
-from sign_vp import sign_vp
-from verify import verify_vc
-from verify_vp import verify_vp
-from utils import now
+from pyvckit.did import generate_keys, generate_did, get_signing_key, gen_did_document
+from pyvckit.sign_vc import sign
+from pyvckit.sign_vp import sign_vp
+from pyvckit.verify import verify_vc
+from pyvckit.verify_vp import verify_vp
+from pyvckit.utils import now
 
 
 def test_generated_did_key():
diff --git a/tests/test_interoperability.py b/tests/test_interoperability.py
index 91a6923..f3caadb 100644
--- a/tests/test_interoperability.py
+++ b/tests/test_interoperability.py
@@ -6,12 +6,12 @@ import didkit
 # import nacl.encoding
 from ast import literal_eval
 
-from sign_vc import sign
-from sign_vp import sign_vp
-from verify import verify_vc
-from verify_vp import verify_vp
-from utils import now
-from did import generate_keys, generate_did, get_signing_key
+from pyvckit.sign_vc import sign
+from pyvckit.sign_vp import sign_vp
+from pyvckit.verify import verify_vc
+from pyvckit.verify_vp import verify_vp
+from pyvckit.utils import now
+from pyvckit.did import generate_keys, generate_did, get_signing_key
 
 
 def verify_credential(vc):