diff --git a/apps/epp_proxy/src/certs.erl b/apps/epp_proxy/src/certs.erl
index fcfcc3e..a04caf4 100644
--- a/apps/epp_proxy/src/certs.erl
+++ b/apps/epp_proxy/src/certs.erl
@@ -1 +1,48 @@
 -module(certs).
+
+-include_lib("public_key/include/public_key.hrl").
+
+-export([read_pem_certificate/1, get_subject_from_otp_certificate/1,
+         get_common_name_from_subject/1, certificate_to_pem/1,
+         read_der_certificate/1]).
+
+%% Read certificate from the wire and return back an otp type record
+read_der_certificate(Der) ->
+    Certificate = public_key:pkix_decode_cert(Der, otp),
+    Certificate.
+
+%% Take an otp record and convert it into a string that can be set into HTTP
+%% header SSL_CLIENT_CERT.
+certificate_to_pem(Certificate) ->
+    PemEntry = {'Certificate', Certificate, not_encrypted},
+    PemString = public_key:pem_encode([PemEntry]),
+    binary:replace(PemString, <<"\n">>, <<" ">>, [global]).
+
+%% Read only a specific type of certificate, otherwise fail.
+get_subject_from_otp_certificate(Certificate) when is_record(Certificate, 'OTPCertificate') ->
+    Subject = Certificate#'OTPCertificate'.tbsCertificate#'OTPTBSCertificate'.subject,
+    Subject.
+
+%% Take a subject rdnSequence that can be set into
+%% HTTP header SSL_CLIENT_S_DN_CN.
+get_common_name_from_subject(Subject) ->
+    CommonName = ?'id-at-commonName',
+    {_Type, Field} = get_field_from_subject(Subject, CommonName),
+    Field.
+
+%% Only used for local development test, is not required for the application.
+read_pem_certificate(PathToCert) ->
+    {ok, PemBin} = file:read_file(PathToCert),
+    PemEntries = public_key:pem_decode(PemBin),
+    {value, CertEntry} = lists:keysearch('Certificate', 1, PemEntries),
+    {_, DerCert, _} = CertEntry,
+    Decoded = public_key:pkix_decode_cert(DerCert, otp),
+    Decoded.
+
+get_field_from_subject({rdnSequence, Attributes}, Field) ->
+    FlatList = lists:flatten(Attributes),
+    ValidAttrs = lists:filter(fun (X) ->
+                                      X#'AttributeTypeAndValue'.type =:= Field
+                              end, FlatList),
+    Attribute = lists:last(ValidAttrs),
+    Attribute#'AttributeTypeAndValue'.value.
diff --git a/apps/epp_proxy/test/certs_SUITE.erl b/apps/epp_proxy/test/certs_SUITE.erl
new file mode 100644
index 0000000..1519bea
--- /dev/null
+++ b/apps/epp_proxy/test/certs_SUITE.erl
@@ -0,0 +1,13 @@
+-module(certs_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+
+-export([all/0]).
+-export([run_eunit/1]).
+
+all() -> [run_eunit].
+
+%% Run Unit tests.
+%% Todo: these should be property tests, not unit tests.
+run_eunit(_Config) ->
+    ok = eunit:test(certs_tests).
diff --git a/apps/epp_proxy/test/certs_tests.erl b/apps/epp_proxy/test/certs_tests.erl
new file mode 100644
index 0000000..7f0abaf
--- /dev/null
+++ b/apps/epp_proxy/test/certs_tests.erl
@@ -0,0 +1,70 @@
+-module(certs_tests).
+
+-include_lib("eunit/include/eunit.hrl").
+-include_lib("public_key/include/public_key.hrl").
+
+-define(exampleCertFile, "fixtures/epp-proxy-test.crt.pem").
+
+read_der_certificate_test() ->
+    PemEntries = public_key:pem_decode(certificate_pem()),
+    {value, CertEntry} = lists:keysearch('Certificate', 1, PemEntries),
+    {_, DerCert, _} = CertEntry,
+    Certificate = certs:read_der_certificate(DerCert),
+    ?assert(is_record(Certificate, 'OTPCertificate')).
+
+get_subject_from_otp_certificate_test() ->
+    Certificate = test_certificate(),
+    Subject = certs:get_subject_from_otp_certificate(Certificate),
+    {rdnSequence, ListOfAttributes} = Subject.
+
+get_common_name_from_subject_test() ->
+    Certificate = test_certificate(),
+    Subject = certs:get_subject_from_otp_certificate(Certificate),
+    CommonName = certs:get_common_name_from_subject(Subject),
+    ?assertEqual(<<"Epp Proxy Test">>, CommonName).
+
+test_certificate() ->
+    PemEntries = public_key:pem_decode(certificate_pem()),
+    {value, CertEntry} = lists:keysearch('Certificate', 1, PemEntries),
+    {_, DerCert, _} = CertEntry,
+    Decoded = public_key:pkix_decode_cert(DerCert, otp),
+    Decoded.
+
+%% Contents from fixtures/epp-proxy-test.crt.pem file
+certificate_pem() ->
+    <<"-----BEGIN CERTIFICATE-----
+MIIGWzCCBEOgAwIBAgICEAEwDQYJKoZIhvcNAQELBQAwgaoxCzAJBgNVBAYTAkVF
+MREwDwYDVQQIDAhIYXJqdW1hYTEQMA4GA1UEBwwHVGFsbGlubjEjMCEGA1UECgwa
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+-----END CERTIFICATE-----">>.
diff --git a/fixtures/epp-proxy-test.crt.pem b/fixtures/epp-proxy-test.crt.pem
new file mode 100644
index 0000000..a45d959
--- /dev/null
+++ b/fixtures/epp-proxy-test.crt.pem
@@ -0,0 +1,36 @@
+-----BEGIN CERTIFICATE-----
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+-----END CERTIFICATE-----
diff --git a/fixtures/epp-proxy-test.key.pem b/fixtures/epp-proxy-test.key.pem
new file mode 100644
index 0000000..0a42e2e
--- /dev/null
+++ b/fixtures/epp-proxy-test.key.pem
@@ -0,0 +1,51 @@
+-----BEGIN RSA PRIVATE KEY-----
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+-----END RSA PRIVATE KEY-----