diff --git a/build.gradle b/build.gradle
index b9129c3..45ba40e 100644
--- a/build.gradle
+++ b/build.gradle
@@ -7,7 +7,7 @@ apply plugin: 'rxjava-project'
 apply plugin: 'java'
 
 dependencies {
-    compile 'io.reactivex:rxjava:1.0.+'
+    compile 'io.reactivex:rxjava:1.0.12'
     testCompile 'junit:junit-dep:4.10'
     testCompile 'org.mockito:mockito-core:1.8.5'
 }
diff --git a/src/main/java/rx/observables/StringObservable.java b/src/main/java/rx/observables/StringObservable.java
index 8beecce..202f008 100644
--- a/src/main/java/rx/observables/StringObservable.java
+++ b/src/main/java/rx/observables/StringObservable.java
@@ -17,6 +17,7 @@
 
 import rx.Observable;
 import rx.Observable.Operator;
+import rx.Producer;
 import rx.Subscriber;
 import rx.functions.Action1;
 import rx.functions.Func0;
@@ -460,40 +461,69 @@ private void output(String part) {
     public static Observable<String> join(final Observable<String> source, final CharSequence separator) {
         return source.lift(new Operator<String, String>() {
             @Override
-            public Subscriber<String> call(final Subscriber<? super String> o) {
-                return new Subscriber<String>(o) {
-                    boolean mayAddSeparator;
-                    StringBuilder b = new StringBuilder();
-
-                    @Override
-                    public void onCompleted() {
-                        String str = b.toString();
-                        b = null;
-                        if (!o.isUnsubscribed())
-                            o.onNext(str);
-                        if (!o.isUnsubscribed())
-                            o.onCompleted();
-                    }
-
-                    @Override
-                    public void onError(Throwable e) {
-                        b = null;
-                        if (!o.isUnsubscribed())
-                            o.onError(e);
-                    }
-
+            public Subscriber<String> call(final Subscriber<? super String> child) {
+                final JoinParentSubscriber parent = new JoinParentSubscriber(child, separator);
+                child.add(parent);
+                child.setProducer(new Producer() {
                     @Override
-                    public void onNext(String t) {
-                        if (mayAddSeparator) {
-                            b.append(separator);
-                        }
-                        mayAddSeparator = true;
-                        b.append(t);
-                    }
-                };
+                    public void request(long n) {
+                       if (n > 0) {
+                           parent.requestAll();
+                       }
+                    }});
+                return parent;
             }
         });
     }
+    
+    private static final class JoinParentSubscriber extends Subscriber<String> {
+        
+        private final Subscriber<? super String> child;
+        private final CharSequence separator;
+        private boolean mayAddSeparator;
+        private StringBuilder b = new StringBuilder();
+        
+        JoinParentSubscriber(Subscriber<? super String> child, CharSequence separator) {
+            this.child = child;
+            this.separator = separator;
+        }
+
+        void requestAll() {
+            request(Long.MAX_VALUE);
+        }
+        
+        @Override
+        public void onStart() {
+            request(0);
+        }
+
+        @Override
+        public void onCompleted() {
+            String str = b.toString();
+            b = null;
+            if (!child.isUnsubscribed())
+                child.onNext(str);
+            if (!child.isUnsubscribed())
+                child.onCompleted();
+        }
+
+        @Override
+        public void onError(Throwable e) {
+            b = null;
+            if (!child.isUnsubscribed())
+                child.onError(e);
+        }
+
+        @Override
+        public void onNext(String t) {
+            if (mayAddSeparator) {
+                b.append(separator);
+            }
+            mayAddSeparator = true;
+            b.append(t);
+        }
+        
+    }
 
     /**
      * Splits the {@link Observable} of Strings by lines and numbers them (zero based index)
diff --git a/src/test/java/rx/observables/StringObservableTest.java b/src/test/java/rx/observables/StringObservableTest.java
index dca6bf6..9be8106 100644
--- a/src/test/java/rx/observables/StringObservableTest.java
+++ b/src/test/java/rx/observables/StringObservableTest.java
@@ -26,6 +26,7 @@
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
+import static rx.Observable.just;
 import static rx.observables.StringObservable.byCharacter;
 import static rx.observables.StringObservable.byLine;
 import static rx.observables.StringObservable.decode;
@@ -456,4 +457,25 @@ public Observable<String> call(Reader reader) {
 
         verify(reader, times(1)).close();
     }
+    
+    @Test(timeout=5000)
+    public void testJoinDoesNotStallIssue23() {
+        String s = StringObservable
+                 .join(just("a","b","c"),",")
+                .toBlocking().single();
+        assertEquals("a,b,c", s);
+    }
+    
+    @Test
+    public void testJoinBackpressure() {
+        TestSubscriber<String> ts = new TestSubscriber<String>(0);
+        StringObservable
+            .join(just("a","b","c"),",")
+            .subscribe(ts);
+        ts.assertNoValues();
+        ts.assertNoTerminalEvent();
+        ts.requestMore(1);
+        ts.assertValues("a,b,c");
+        ts.assertCompleted();
+    }
 }