diff --git a/discovery_test.go b/discovery_test.go
index 55a048b..7ff5619 100644
--- a/discovery_test.go
+++ b/discovery_test.go
@@ -7,18 +7,20 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-var testAdvertisementSleepDuration = time.Millisecond * 100
+var testAdvertPropagationDelay = time.Millisecond * 100
 
 func TestHost_Discover(t *testing.T) {
-	ha := newHost(t, basicTestConfig(t))
+	namespaces := []string{"", "test"}
+
+	ha := newHost(t, basicTestConfig(t, namespaces))
 	err := ha.Start()
 	require.NoError(t, err)
 
-	hb := newHost(t, basicTestConfig(t))
+	hb := newHost(t, basicTestConfig(t, namespaces))
 	err = hb.Start()
 	require.NoError(t, err)
 
-	hc := newHost(t, basicTestConfig(t))
+	hc := newHost(t, basicTestConfig(t, namespaces))
 	err = hc.Start()
 	require.NoError(t, err)
 
@@ -29,17 +31,15 @@ func TestHost_Discover(t *testing.T) {
 	err = hc.h.Connect(hc.ctx, hb.AddrInfo())
 	require.NoError(t, err)
 
-	require.GreaterOrEqual(t, len(ha.h.Network().Peers()), 1)
+	// now that the nodes can form a DHT, advertise
+	ha.Advertise()
+	hb.Advertise()
+	hc.Addresses()
+	time.Sleep(testAdvertPropagationDelay)
+
+	require.GreaterOrEqual(t, len(ha.h.Network().Peers()), 2)
 	require.GreaterOrEqual(t, len(hb.h.Network().Peers()), 2)
-	require.GreaterOrEqual(t, len(hc.h.Network().Peers()), 1)
-
-	providedNamesapces := func() []string {
-		return []string{"test"}
-	}
-	ha.SetAdvertisedNamespacesFunc(providedNamesapces)
-	hb.SetAdvertisedNamespacesFunc(providedNamesapces)
-	hc.SetAdvertisedNamespacesFunc(providedNamesapces)
-	time.Sleep(testAdvertisementSleepDuration)
+	require.GreaterOrEqual(t, len(hc.h.Network().Peers()), 2)
 
 	peerIDs, err := hc.Discover("test", time.Second)
 	require.NoError(t, err)
diff --git a/host.go b/host.go
index a10b429..8c30a57 100644
--- a/host.go
+++ b/host.go
@@ -51,6 +51,11 @@ type Config struct {
 	Bootnodes  []string
 	ProtocolID string
 	ListenIP   string
+
+	// AdvertisedNamespacesFunc is called to determine which namespaces should
+	// be advertised in the DHT. In most use cases, the passed function should,
+	// at minimum, return the empty ("") namespace.
+	AdvertisedNamespacesFunc func() []string
 }
 
 // QUIC will have better performance in high-bandwidth protocols if you increase a socket
@@ -152,11 +157,12 @@ func NewHost(cfg *Config) (*Host, error) {
 		ds:         ds,
 		bootnodes:  bns,
 		discovery: &discovery{
-			ctx:         ourCtx,
-			dht:         dht,
-			h:           routedHost,
-			rd:          libp2pdiscovery.NewRoutingDiscovery(dht),
-			advertiseCh: make(chan struct{}),
+			ctx:                  ourCtx,
+			dht:                  dht,
+			h:                    routedHost,
+			rd:                   libp2pdiscovery.NewRoutingDiscovery(dht),
+			advertiseCh:          make(chan struct{}),
+			advertisedNamespaces: cfg.AdvertisedNamespacesFunc,
 		},
 	}
 
@@ -264,13 +270,6 @@ func (h *Host) SetStreamHandler(pid string, handler func(libp2pnetwork.Stream))
 	log.Debugf("supporting protocol %s", protocol.ID(h.protocolID+pid))
 }
 
-// SetAdvertisedNamespacesFunc sets the function that is called to determine
-// which namespaces should be advertised in the DHT. In most use cases, the
-// passed function should, at minimum, return the empty ("") namespace.
-func (h *Host) SetAdvertisedNamespacesFunc(fn func() []string) {
-	h.discovery.setAdvertisedNamespacesFunc(fn)
-}
-
 // Connectedness returns the connectedness state of a given peer.
 func (h *Host) Connectedness(who peer.ID) libp2pnetwork.Connectedness {
 	return h.h.Network().Connectedness(who)
diff --git a/host_test.go b/host_test.go
index 6cce2f8..1b51adc 100644
--- a/host_test.go
+++ b/host_test.go
@@ -17,7 +17,7 @@ func init() {
 	_ = logging.SetLogLevel("p2pnet", "debug")
 }
 
-func basicTestConfig(t *testing.T) *Config {
+func basicTestConfig(t *testing.T, namespaces []string) *Config {
 	// t.TempDir() is unique on every call. Don't reuse this config with multiple hosts.
 	tmpDir := t.TempDir()
 	return &Config{
@@ -27,6 +27,9 @@ func basicTestConfig(t *testing.T) *Config {
 		KeyFile:   path.Join(tmpDir, "node.key"),
 		Bootnodes: nil,
 		ListenIP:  "127.0.0.1",
+		AdvertisedNamespacesFunc: func() []string {
+			return namespaces
+		},
 	}
 }
 
@@ -41,7 +44,7 @@ func newHost(t *testing.T, cfg *Config) *Host {
 }
 
 func TestNewHost(t *testing.T) {
-	h := newHost(t, basicTestConfig(t))
+	h := newHost(t, basicTestConfig(t, []string{""}))
 	err := h.Start()
 	require.NoError(t, err)
 
@@ -53,40 +56,37 @@ func TestNewHost(t *testing.T) {
 }
 
 func TestAdvertiseDiscover(t *testing.T) {
-	h1 := newHost(t, basicTestConfig(t))
+	nameSpaces := []string{"", "one", "two", "three"}
+
+	h1 := newHost(t, basicTestConfig(t, nameSpaces))
 	err := h1.Start()
 	require.NoError(t, err)
 
 	h1Addresses := h1.Addresses()
 	require.NotEmpty(t, h1Addresses)
 
-	cfgH2 := basicTestConfig(t)
+	cfgH2 := basicTestConfig(t, nameSpaces)
 	cfgH2.Bootnodes = []string{h1Addresses[0].String()}
 
 	h2 := newHost(t, cfgH2)
 	err = h2.Start()
 	require.NoError(t, err)
 
-	nameSpaces := []string{"", "one", "two", "three"}
-	advertisedNamespaces := func() []string {
-		return nameSpaces
-	}
-	h1.SetAdvertisedNamespacesFunc(advertisedNamespaces)
-
-	// Advertise only puts the namespaces to advertise into a channel. It
-	// doesn't block until the advertisements are actually sent.
-	time.Sleep(500 * time.Millisecond)
+	// h1's first advertisement attempt failed, as h2 was not yet online to
+	// form a DHT with. Run h1's advertisement loop now instead of waiting.
+	h1.Advertise()
+	time.Sleep(testAdvertPropagationDelay)
 
 	for _, ns := range nameSpaces {
 		peerIDs, err := h2.Discover(ns, time.Second*3)
-		require.NoError(t, err)
-		require.Len(t, peerIDs, 1)
-		require.Equal(t, h1.PeerID(), peerIDs[0])
+		require.NoError(t, err, "namespace=%q", ns)
+		require.Len(t, peerIDs, 1, "namespace=%q", ns)
+		require.Equal(t, h1.PeerID(), peerIDs[0], "namespace=%q", ns)
 	}
 }
 
 func TestHost_ConnectToSelf(t *testing.T) {
-	h := newHost(t, basicTestConfig(t))
+	h := newHost(t, basicTestConfig(t, nil))
 	err := h.Start()
 	require.NoError(t, err)