diff --git a/README.macosx b/README.macosx
index 25794d8..cfda4b8 100644
--- a/README.macosx
+++ b/README.macosx
@@ -17,12 +17,17 @@ devfs is based on an older (non-default) FreeBSD devfs, and that version
 of devfs cannot be configured to set the permissions and/or ownership of
 those devices.
 
-Therefore, we supply a "startup item" for OS X that will change the
-ownership of the BPF devices so that the "admin" group owns them, and
-will change the permission of the BPF devices to rw-rw----, so that all
-users in the "admin" group - i.e., all users with "Allow user to
-administer this computer" turned on - have both read and write access to
-them.
+Therefore, we supply:
+
+	a "startup item" for older versions of Mac OS X;
+
+	a launchd daemon for Tiger and later versions of Mac OS X;
+
+Both of them will change the ownership of the BPF devices so that the
+"admin" group owns them, and will change the permission of the BPF
+devices to rw-rw----, so that all users in the "admin" group - i.e., all
+users with "Allow user to administer this computer" turned on - have
+both read and write access to them.
 
 The startup item is in the ChmodBPF directory in the source tree.  A
 /Library/StartupItems directory should be created if it doesn't already
@@ -30,7 +35,28 @@ exist, and the ChmodBPF directory should be copied to the
 /Library/StartupItems directory (copy the entire directory, so that
 there's a /Library/StartupItems/ChmodBPF directory, containing all the
 files in the source tree's ChmodBPF directory; don't copy the individual
-items in that directory to /Library/StartupItems).
+items in that directory to /Library/StartupItems).  The ChmodBPF
+directory, and all files under it, must be owned by root.  Installing
+the files won't immediately cause the startup item to be executed; it
+will be executed on the next reboot.  To change the permissions before
+the reboot, run
+
+	sudo SystemStarter start ChmodBPF
+
+The launchd daemon is the chmod_bpf script, plus the
+org.tcpdump.chmod_bpf.plist launchd plist file.  chmod_bpf should be
+installed in /usr/local/bin/chmod_bpf, and org.tcpdump.chmod_bpf.plist
+should be installed in /Library/LaunchDaemons.  chmod_bpf, and
+org.tcpdump.chmod_bpf.plist, must be owned by root.  Installing the
+script and plist file won't immediately cause the script to be executed;
+it will be executed on the next reboot.  To change the permissions
+before the reboot, run
+
+	sudo /usr/local/bin/chmod_bpf
+
+or
+
+	sudo launchctl load /Library/LaunchDaemons/org.tcpdump.chmod_bpf.plist
 
 If you want to give a particular user permission to access the BPF
 devices, rather than giving all administrative users permission to