diff --git a/spec/integration/subcommand_spec.cr b/spec/integration/subcommand_spec.cr
new file mode 100644
index 00000000..89226a04
--- /dev/null
+++ b/spec/integration/subcommand_spec.cr
@@ -0,0 +1,41 @@
+require "./spec_helper"
+
+describe "subcommand" do
+  it "forwards all arguments to subcommand" do
+    create_shard("dummy", "0.1.0")
+    {% if flag?(:win32) %}
+      create_executable "dummy", "bin/shards-dummy", %(print ARGV.join(" "))
+    {% else %}
+      path = create_file("dummy", "bin/shards-dummy", "#!/bin/sh\necho $@\n")
+      File.chmod(path, 0o755)
+    {% end %}
+
+    with_path(git_path("dummy/bin")) do
+      output = run("shards dummy --no-color --verbose --unknown other argument")
+      output.should contain(%(--no-color --verbose --unknown other argument))
+    end
+  end
+
+  it "correctly forwards '--help' option to subcommand" do
+    create_shard("dummy", "0.1.0")
+    {% if flag?(:win32) %}
+      create_executable "dummy", "bin/shards-dummy", %(print ARGV.join(" "))
+    {% else %}
+      path = create_file("dummy", "bin/shards-dummy", "#!/bin/sh\necho $@\n")
+      File.chmod(path, 0o755)
+    {% end %}
+
+    with_path(git_path("dummy/bin")) do
+      output = run("shards dummy --help")
+      output.should contain(%(--help))
+    end
+  end
+end
+
+private def with_path(path)
+  old_path = ENV["PATH"]
+  ENV["PATH"] = "#{File.expand_path(path)}#{Process::PATH_DELIMITER}#{ENV["PATH"]}"
+  yield
+ensure
+  ENV["PATH"] = old_path
+end
diff --git a/src/cli.cr b/src/cli.cr
index 668c825e..beb8ad24 100644
--- a/src/cli.cr
+++ b/src/cli.cr
@@ -26,6 +26,8 @@ module Shards
   end
 
   def self.run
+    display_help = false
+
     OptionParser.parse(cli_options) do |opts|
       path = Dir.current
 
@@ -53,7 +55,7 @@ module Shards
       opts.on("--ignore-crystal-version", "Has no effect. Kept for compatibility, to be removed in the future.") { }
       opts.on("-v", "--verbose", "Increase the log verbosity, printing all debug statements.") { self.set_debug_log_level }
       opts.on("-q", "--quiet", "Decrease the log verbosity, printing only warnings and errors.") { self.set_warning_log_level }
-      opts.on("-h", "--help", "Print usage synopsis.") { self.display_help_and_exit(opts) }
+      opts.on("-h", "--help", "Print usage synopsis.") { display_help = true }
 
       opts.unknown_args do |args, options|
         case args[0]? || DEFAULT_COMMAND
@@ -101,12 +103,16 @@ module Shards
         else
           program_name = "shards-#{args[0]}"
           if program_path = Process.find_executable(program_name)
-            run_shards_subcommand(program_path, args)
+            run_shards_subcommand(program_path, cli_options)
           else
             display_help_and_exit(opts)
           end
         end
 
+        if display_help
+          display_help_and_exit(opts)
+        end
+
         exit
       end
     end
@@ -119,7 +125,7 @@ module Shards
     {% else %}
       shards_opts = ENV.fetch("SHARDS_OPTS", "").split
     {% end %}
-    ARGV.concat(shards_opts)
+    ARGV.dup.concat(shards_opts)
   end
 
   def self.run_shards_subcommand(process_name, args)