diff --git a/src/publisher.spec.ts b/src/publisher.spec.ts
index bb6f86c9..099c2c76 100644
--- a/src/publisher.spec.ts
+++ b/src/publisher.spec.ts
@@ -105,4 +105,32 @@ describe('Publish Spec', () => {
       expect(p.publish).to.be.a('function');
     });
   });
+
+  context('when a bearer token is provided', () => {
+    context("and specifies a username or password", () => {
+      it('should fail with an error', () => {
+        expect(() =>
+          publisherFactory({
+            pactBroker: 'http://localhost',
+            pactFilesOrDirs: [relativePath],
+            consumerVersion: '1.0.0',
+            pactBrokerToken: "1234",
+            pactBrokerUsername: "username",
+            pactBrokerPassword: "5678",
+          })
+        ).to.throw(Error)
+      });
+
+    });
+    it('should not fail', () => {
+      const p = publisherFactory({
+        pactBroker: 'http://localhost',
+        pactFilesOrDirs: [pactFile],
+        consumerVersion: '1.0.0',
+        pactBrokerToken: "1234"
+      });
+      expect(p).to.be.ok;
+      expect(p.publish).to.be.a('function');
+    });
+  });
 });
diff --git a/src/publisher.ts b/src/publisher.ts
index 9db2bc92..071a6a56 100644
--- a/src/publisher.ts
+++ b/src/publisher.ts
@@ -86,6 +86,12 @@ export class Publisher {
       );
     }
 
+    if (options.pactBrokerToken && (options.pactBrokerUsername || options.pactBrokerPassword)) {
+      throw new Error(
+        'Must provide pactBrokerToken or pactBrokerUsername/pactBrokerPassword but not both.',
+      );
+    }
+
     this.options = options;
   }
 
diff --git a/src/verifier.spec.ts b/src/verifier.spec.ts
index 573803ee..35722b32 100644
--- a/src/verifier.spec.ts
+++ b/src/verifier.spec.ts
@@ -318,4 +318,29 @@ describe('Verifier Spec', () => {
       ).to.not.throw(Error);
     });
   });
+
+  context('when using a bearer token', () => {
+    context('and specifies a username or password', () => {
+      it('should fail with an error', () => {
+        expect(() =>
+          verifierFactory({
+            providerBaseUrl: 'http://localhost',
+            pactUrls: ['http://idontexist'],
+            pactBrokerToken: "1234",
+            pactBrokerUsername: "username",
+            pactBrokerPassword: "5678",
+          }),
+        ).to.throw(Error);
+      });
+    });
+    it('should not fail', () => {
+      const v = verifierFactory({
+        providerBaseUrl: 'http://localhost',
+        pactUrls: ['http://idontexist'],
+        pactBrokerToken: "1234",
+      })
+
+      expect(v.options.pactBrokerToken).to.eq("1234");
+    });
+  });
 });
diff --git a/src/verifier.ts b/src/verifier.ts
index 40abd7ec..3c4bf879 100644
--- a/src/verifier.ts
+++ b/src/verifier.ts
@@ -121,6 +121,12 @@ export class Verifier {
       checkTypes.assert.string(options.pactBrokerPassword);
     }
 
+    if (options.pactBrokerToken && (options.pactBrokerUsername || options.pactBrokerPassword)) {
+      throw new Error(
+        'Must provide pactBrokerToken or pactBrokerUsername/pactBrokerPassword but not both.',
+      );
+    }
+
     if (options.pactBrokerUrl) {
       checkTypes.assert.string(options.pactBrokerUrl);
     }