diff --git a/Makefile b/Makefile
index efa73b2..28da815 100644
--- a/Makefile
+++ b/Makefile
@@ -11,6 +11,8 @@ smoketest-tinygo:
 	@md5sum test.hex
 	$(TINYGO) build -o test.uf2 -size=short -target=circuitplay-bluefruit ./examples/circuitplay
 	@md5sum test.hex
+	$(TINYGO) build -o test.hex -size=short -target=circuitplay-bluefruit ./examples/connparams
+	@md5sum test.hex
 	$(TINYGO) build -o test.uf2 -size=short -target=circuitplay-bluefruit ./examples/discover
 	@md5sum test.hex
 	$(TINYGO) build -o test.hex -size=short -target=pca10040-s132v6       ./examples/heartrate
@@ -42,6 +44,7 @@ smoketest-tinygo:
 smoketest-linux:
 	# Test on Linux.
 	GOOS=linux go build -o /tmp/go-build-discard ./examples/advertisement
+	GOOS=linux go build -o /tmp/go-build-discard ./examples/connparams
 	GOOS=linux go build -o /tmp/go-build-discard ./examples/heartrate
 	GOOS=linux go build -o /tmp/go-build-discard ./examples/heartrate-monitor
 	GOOS=linux go build -o /tmp/go-build-discard ./examples/nusserver
diff --git a/examples/connparams/main.go b/examples/connparams/main.go
new file mode 100644
index 0000000..762cbb9
--- /dev/null
+++ b/examples/connparams/main.go
@@ -0,0 +1,84 @@
+// Test for setting connection parameters.
+//
+// To test this feature, run this either on a desktop OS or by flashing it to a
+// device with TinyGo. Then connect to it from a BLE connection debugger, for
+// example nRF Connect on Android. After a second, you should see in the log of
+// the BLE app that the connection latency has been updated. It might look
+// something like this:
+//
+//	Connection parameters updated (interval: 510.0ms, latency: 0, timeout: 10000ms)
+package main
+
+import (
+	"time"
+
+	"tinygo.org/x/bluetooth"
+)
+
+var (
+	adapter   = bluetooth.DefaultAdapter
+	newDevice chan bluetooth.Device
+)
+
+func main() {
+	must("enable BLE stack", adapter.Enable())
+
+	newDevice = make(chan bluetooth.Device, 1)
+	adapter.SetConnectHandler(func(device bluetooth.Device, connected bool) {
+		// If this is a new device, signal it to the separate goroutine.
+		if connected {
+			select {
+			case newDevice <- device:
+			default:
+			}
+		}
+	})
+
+	// Start advertising, so we can be found.
+	const name = "Go BLE test"
+	adv := adapter.DefaultAdvertisement()
+	adv.Configure(bluetooth.AdvertisementOptions{
+		LocalName: name,
+	})
+	adv.Start()
+	println("advertising:", name)
+
+	for device := range newDevice {
+		println("connection from device:", device.Address.String())
+
+		// Discover services and characteristics.
+		svcs, err := device.DiscoverServices(nil)
+		if err != nil {
+			println("  failed to resolve services:", err)
+		}
+		for _, svc := range svcs {
+			println("  service:", svc.UUID().String())
+			chars, err := svc.DiscoverCharacteristics(nil)
+			if err != nil {
+				println("    failed to resolve characteristics:", err)
+			}
+			for _, char := range chars {
+				println("    characteristic:", char.UUID().String())
+			}
+		}
+
+		// Update connection parameters (as a test).
+		time.Sleep(time.Second)
+		err = device.RequestConnectionParams(bluetooth.ConnectionParams{
+			MinInterval: bluetooth.NewDuration(495 * time.Millisecond),
+			MaxInterval: bluetooth.NewDuration(510 * time.Millisecond),
+			Timeout:     bluetooth.NewDuration(10 * time.Second),
+		})
+		if err != nil {
+			println("  failed to update connection parameters:", err)
+			continue
+		}
+		println("  updated connection parameters")
+	}
+}
+
+func must(action string, err error) {
+	if err != nil {
+		panic("failed to " + action + ": " + err.Error())
+	}
+}
diff --git a/gap.go b/gap.go
index 17dddfd..f6a418c 100644
--- a/gap.go
+++ b/gap.go
@@ -391,7 +391,8 @@ func (buf *rawAdvertisementPayload) addServiceUUID(uuid UUID) (ok bool) {
 	}
 }
 
-// ConnectionParams are used when connecting to a peripherals.
+// ConnectionParams are used when connecting to a peripherals or when changing
+// the parameters of an active connection.
 type ConnectionParams struct {
 	// The timeout for the connection attempt. Not used during the rest of the
 	// connection. If no duration is specified, a default timeout will be used.
@@ -403,4 +404,9 @@ type ConnectionParams struct {
 	// will be used.
 	MinInterval Duration
 	MaxInterval Duration
+
+	// Connection Supervision Timeout. After this time has passed with no
+	// communication, the connection is considered lost. If no timeout is
+	// specified, the timeout will be unchanged.
+	Timeout Duration
 }
diff --git a/gap_darwin.go b/gap_darwin.go
index c87db05..542535c 100644
--- a/gap_darwin.go
+++ b/gap_darwin.go
@@ -176,6 +176,18 @@ func (d Device) Disconnect() error {
 	return nil
 }
 
+// RequestConnectionParams requests a different connection latency and timeout
+// of the given device connection. Fields that are unset will be left alone.
+// Whether or not the device will actually honor this, depends on the device and
+// on the specific parameters.
+//
+// This call has not yet been implemented on macOS.
+func (d Device) RequestConnectionParams(params ConnectionParams) error {
+	// TODO: implement this using setDesiredConnectionLatency, see:
+	// https://developer.apple.com/documentation/corebluetooth/cbperipheralmanager/1393277-setdesiredconnectionlatency
+	return nil
+}
+
 // Peripheral delegate functions
 
 type peripheralDelegate struct {
diff --git a/gap_linux.go b/gap_linux.go
index 2c77c36..80ecf1a 100644
--- a/gap_linux.go
+++ b/gap_linux.go
@@ -366,3 +366,14 @@ func (d Device) Disconnect() error {
 	// property change in `watchForConnect` and cancel things then
 	return d.device.Call("org.bluez.Device1.Disconnect", 0).Err
 }
+
+// RequestConnectionParams requests a different connection latency and timeout
+// of the given device connection. Fields that are unset will be left alone.
+// Whether or not the device will actually honor this, depends on the device and
+// on the specific parameters.
+//
+// On Linux, this call doesn't do anything because BlueZ doesn't support
+// changing the connection latency.
+func (d Device) RequestConnectionParams(params ConnectionParams) error {
+	return nil
+}
diff --git a/gap_ninafw.go b/gap_ninafw.go
index 51fbbf5..5cf7840 100644
--- a/gap_ninafw.go
+++ b/gap_ninafw.go
@@ -230,6 +230,16 @@ func (d Device) Disconnect() error {
 	return nil
 }
 
+// RequestConnectionParams requests a different connection latency and timeout
+// of the given device connection. Fields that are unset will be left alone.
+// Whether or not the device will actually honor this, depends on the device and
+// on the specific parameters.
+//
+// On NINA, this call hasn't been implemented yet.
+func (d Device) RequestConnectionParams(params ConnectionParams) error {
+	return nil
+}
+
 func (d Device) findNotificationRegistration(handle uint16) *notificationRegistration {
 	for _, n := range d.notificationRegistrations {
 		if n.handle == handle {
diff --git a/gap_nrf528xx-central.go b/gap_nrf528xx-central.go
index b451573..085e7d0 100644
--- a/gap_nrf528xx-central.go
+++ b/gap_nrf528xx-central.go
@@ -188,3 +188,34 @@ func (d Device) Disconnect() error {
 
 	return nil
 }
+
+// RequestConnectionParams requests a different connection latency and timeout
+// of the given device connection. Fields that are unset will be left alone.
+// Whether or not the device will actually honor this, depends on the device and
+// on the specific parameters.
+//
+// On the Nordic SoftDevice, this call will also set the slave latency to 0.
+func (d Device) RequestConnectionParams(params ConnectionParams) error {
+	// The default parameters if no specific parameters are picked.
+	connParams := C.ble_gap_conn_params_t{
+		min_conn_interval: C.BLE_GAP_CP_MIN_CONN_INTVL_NONE,
+		max_conn_interval: C.BLE_GAP_CP_MAX_CONN_INTVL_NONE,
+		slave_latency:     0,
+		conn_sup_timeout:  C.BLE_GAP_CP_CONN_SUP_TIMEOUT_NONE,
+	}
+
+	// Use specified parameters if available.
+	if params.MinInterval != 0 {
+		connParams.min_conn_interval = C.uint16_t(params.MinInterval) / 2
+	}
+	if params.MaxInterval != 0 {
+		connParams.max_conn_interval = C.uint16_t(params.MaxInterval) / 2
+	}
+	if params.Timeout != 0 {
+		connParams.conn_sup_timeout = C.uint16_t(params.Timeout) / 16
+	}
+
+	// Send them to peer device.
+	errCode := C.sd_ble_gap_conn_param_update(d.connectionHandle, &connParams)
+	return makeError(errCode)
+}
diff --git a/gap_windows.go b/gap_windows.go
index 5ae0f97..c800c25 100644
--- a/gap_windows.go
+++ b/gap_windows.go
@@ -247,3 +247,15 @@ func (d Device) Disconnect() error {
 
 	return nil
 }
+
+// RequestConnectionParams requests a different connection latency and timeout
+// of the given device connection. Fields that are unset will be left alone.
+// Whether or not the device will actually honor this, depends on the device and
+// on the specific parameters.
+//
+// On Windows, this call doesn't do anything.
+func (d Device) RequestConnectionParams(params ConnectionParams) error {
+	// TODO: implement this using
+	// BluetoothLEDevice.RequestPreferredConnectionParameters.
+	return nil
+}