diff --git a/test/test_integration_pending.rb b/test/test_integration_pending.rb
index 1a25910b..467ed0a2 100644
--- a/test/test_integration_pending.rb
+++ b/test/test_integration_pending.rb
@@ -3,6 +3,39 @@
 require "benchmark"
 
 class IntegrationPendingTestCase < SQLite3::TestCase
+  class ThreadSynchronizer
+    def initialize
+      @main_to_thread = Queue.new
+      @thread_to_main = Queue.new
+    end
+
+    def send_to_thread state
+      @main_to_thread.push state
+    end
+
+    def send_to_main state
+      @thread_to_main.push state
+    end
+
+    def wait_for_thread expected_state
+      state = @thread_to_main.pop
+      raise "Invalid state #{state}. #{expected_state} is expected" if state != expected_state
+    end
+
+    def wait_for_main expected_state
+      state = @main_to_thread.pop
+      raise "Invalid state #{state}. #{expected_state} is expected" if state != expected_state
+    end
+
+    def close_thread
+      @thread_to_main.close
+    end
+
+    def close_main
+      @main_to_thread.close
+    end
+  end
+
   def setup
     @db = SQLite3::Database.new("test.db")
     @db.transaction do
@@ -19,19 +52,20 @@ def teardown
   end
 
   def test_busy_handler_impatient
-    busy = Mutex.new
-    busy.lock
+    synchronizer = ThreadSynchronizer.new
     handler_call_count = 0
 
-    t = Thread.new do
+    t = Thread.new(synchronizer) do |sync|
       db2 = SQLite3::Database.open("test.db")
       db2.transaction(:exclusive) do
-        busy.lock
+        sync.send_to_main :ready_0
+        sync.wait_for_main :end_1
       end
     ensure
       db2&.close
+      sync.close_thread
     end
-    sleep 1
+    synchronizer.wait_for_thread :ready_0
 
     @db.busy_handler do
       handler_call_count += 1
@@ -42,7 +76,8 @@ def test_busy_handler_impatient
       @db.execute "insert into foo (b) values ( 'from 2' )"
     end
 
-    busy.unlock
+    synchronizer.send_to_thread :end_1
+    synchronizer.close_main
     t.join
 
     assert_equal 1, handler_call_count
@@ -50,26 +85,28 @@ def test_busy_handler_impatient
 
   def test_busy_timeout
     @db.busy_timeout 1000
-    busy = Mutex.new
-    busy.lock
+    synchronizer = ThreadSynchronizer.new
 
-    t = Thread.new do
+    t = Thread.new(synchronizer) do |sync|
       db2 = SQLite3::Database.open("test.db")
       db2.transaction(:exclusive) do
-        busy.lock
+        sync.send_to_main :ready_0
+        sync.wait_for_main :end_1
       end
     ensure
       db2&.close
+      sync.close_thread
     end
 
-    sleep 1
+    synchronizer.wait_for_thread :ready_0
     time = Benchmark.measure do
       assert_raise(SQLite3::BusyException) do
         @db.execute "insert into foo (b) values ( 'from 2' )"
       end
     end
 
-    busy.unlock
+    synchronizer.send_to_thread :end_1
+    synchronizer.close_main
     t.join
 
     assert_operator time.real * 1000, :>=, 1000
@@ -110,4 +147,38 @@ def test_busy_handler_timeout_releases_gvl
 
     assert_operator work.size - work.find_index("|"), :>, 3
   end
+
+  def test_busy_handler_outwait
+    synchronizer = ThreadSynchronizer.new
+    handler_call_count = 0
+
+    t = Thread.new(synchronizer) do |sync|
+      db2 = SQLite3::Database.open("test.db")
+      db2.transaction(:exclusive) do
+        sync.send_to_main :ready_0
+        sync.wait_for_main :busy_handler_called_1
+      end
+      sync.send_to_main :end_of_transaction_2
+    ensure
+      db2&.close
+      sync.close_thread
+    end
+
+    @db.busy_handler do |count|
+      handler_call_count += 1
+      synchronizer.send_to_thread :busy_handler_called_1
+      synchronizer.wait_for_thread :end_of_transaction_2
+      true
+    end
+
+    synchronizer.wait_for_thread :ready_0
+    assert_nothing_raised do
+      @db.execute "insert into foo (b) values ( 'from 2' )"
+    end
+
+    synchronizer.close_main
+    t.join
+
+    assert_equal 1, handler_call_count
+  end
 end