diff --git a/internal/pkg/commands/devices.go b/internal/pkg/commands/devices.go
new file mode 100644
index 0000000..a6836cf
--- /dev/null
+++ b/internal/pkg/commands/devices.go
@@ -0,0 +1,535 @@
+/*
+ * Copyright 2019-present Ciena Corporation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package commands
+
+import (
+	"context"
+	"fmt"
+	"github.com/ciena/voltctl/pkg/format"
+	"github.com/ciena/voltctl/pkg/model"
+	"github.com/fullstorydev/grpcurl"
+	flags "github.com/jessevdk/go-flags"
+	"github.com/jhump/protoreflect/dynamic"
+	"strings"
+)
+
+const (
+	DEFAULT_DEVICE_FORMAT         = "table{{ .Id }}\t{{.Type}}\t{{.Root}}\t{{.ParentId}}\t{{.SerialNumber}}\t{{.Vlan}}\t{{.AdminState}}\t{{.OperStatus}}\t{{.ConnectStatus}}"
+	DEFAULT_DEVICE_PORTS_FORMAT   = "table{{.PortNo}}\t{{.Label}}\t{{.Type}}\t{{.AdminState}}\t{{.OperStatus}}\t{{.DeviceId}}\t{{.Peers}}"
+	DEFAULT_DEVICE_INSPECT_FORMAT = `ID: {{.Id}}
+  TYPE:          {{.Type}}
+  ROOT:          {{.Root}}
+  PARENTID:      {{.ParentId}}
+  SERIALNUMBER:  {{.SerialNumber}}
+  VLAN:          {{.Vlan}}
+  ADMINSTATE:    {{.AdminState}}
+  OPERSTATUS:    {{.OperStatus}}
+  CONNECTSTATUS: {{.ConnectStatus}}`
+)
+
+type DeviceList struct {
+	ListOutputOptions
+}
+
+type DeviceCreate struct {
+	DeviceType  string `short:"t" long:"devicetype" default:"simulated_olt" description:"Device type"`
+	MACAddress  string `short:"m" long:"macaddress" default:"00:0c:e2:31:40:00" description:"MAC Address"`
+	IPAddress   string `short:"i" long:"ipaddress" default:"" description:"IP Address"`
+	HostAndPort string `short:"H" long:"hostandport" default:"" description:"Host and port"`
+}
+
+type DeviceId string
+
+type DeviceDelete struct {
+	Args struct {
+		Ids []DeviceId `positional-arg-name:"DEVICE_ID" required:"yes"`
+	} `positional-args:"yes"`
+}
+
+type DeviceEnable struct {
+	Args struct {
+		Ids []DeviceId `positional-arg-name:"DEVICE_ID" required:"yes"`
+	} `positional-args:"yes"`
+}
+
+type DeviceDisable struct {
+	Args struct {
+		Ids []DeviceId `positional-arg-name:"DEVICE_ID" required:"yes"`
+	} `positional-args:"yes"`
+}
+
+type DeviceReboot struct {
+	Args struct {
+		Ids []DeviceId `positional-arg-name:"DEVICE_ID" required:"yes"`
+	} `positional-args:"yes"`
+}
+
+type DeviceFlowList struct {
+	ListOutputOptions
+	Args struct {
+		Id DeviceId `positional-arg-name:"DEVICE_ID" required:"yes"`
+	} `positional-args:"yes"`
+}
+
+type DevicePortList struct {
+	ListOutputOptions
+	Args struct {
+		Id DeviceId `positional-arg-name:"DEVICE_ID" required:"yes"`
+	} `positional-args:"yes"`
+}
+
+type DeviceInspect struct {
+	OutputOptionsJson
+	Args struct {
+		Id DeviceId `positional-arg-name:"DEVICE_ID" required:"yes"`
+	} `positional-args:"yes"`
+}
+
+type DeviceOpts struct {
+	List    DeviceList     `command:"list"`
+	Create  DeviceCreate   `command:"create"`
+	Delete  DeviceDelete   `command:"delete"`
+	Enable  DeviceEnable   `command:"enable"`
+	Disable DeviceDisable  `command:"disable"`
+	Flows   DeviceFlowList `command:"flows"`
+	Ports   DevicePortList `command:"ports"`
+	Inspect DeviceInspect  `command:"inspect"`
+	Reboot  DeviceReboot   `command:"reboot"`
+}
+
+var deviceOpts = DeviceOpts{}
+
+func RegisterDeviceCommands(parser *flags.Parser) {
+	parser.AddCommand("device", "device commands", "Commands to query and manipulate VOLTHA devices", &deviceOpts)
+}
+
+func (i *DeviceId) Complete(match string) []flags.Completion {
+	conn, err := NewConnection()
+	if err != nil {
+		return nil
+	}
+	defer conn.Close()
+
+	descriptor, method, err := GetMethod("device-list")
+	if err != nil {
+		return nil
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
+	defer cancel()
+
+	h := &RpcEventHandler{}
+	err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
+	if err != nil {
+		return nil
+	}
+
+	if h.Status != nil && h.Status.Err() != nil {
+		return nil
+	}
+
+	d, err := dynamic.AsDynamicMessage(h.Response)
+	if err != nil {
+		return nil
+	}
+
+	items, err := d.TryGetFieldByName("items")
+	if err != nil {
+		return nil
+	}
+
+	list := make([]flags.Completion, 0)
+	for _, item := range items.([]interface{}) {
+		val := item.(*dynamic.Message)
+		id := val.GetFieldByName("id").(string)
+		if strings.HasPrefix(id, match) {
+			list = append(list, flags.Completion{Item: id})
+		}
+	}
+
+	return list
+}
+
+func (options *DeviceList) Execute(args []string) error {
+
+	conn, err := NewConnection()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	descriptor, method, err := GetMethod("device-list")
+	if err != nil {
+		return err
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
+	defer cancel()
+
+	h := &RpcEventHandler{}
+	err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
+	if err != nil {
+		return err
+	}
+
+	if h.Status != nil && h.Status.Err() != nil {
+		return h.Status.Err()
+	}
+
+	d, err := dynamic.AsDynamicMessage(h.Response)
+	if err != nil {
+		return err
+	}
+
+	items, err := d.TryGetFieldByName("items")
+	if err != nil {
+		return err
+	}
+
+	outputFormat := CharReplacer.Replace(options.Format)
+	if outputFormat == "" {
+		outputFormat = DEFAULT_DEVICE_FORMAT
+	}
+	if options.Quiet {
+		outputFormat = "{{.Id}}"
+	}
+
+	data := make([]model.Device, len(items.([]interface{})))
+	for i, item := range items.([]interface{}) {
+		val := item.(*dynamic.Message)
+		data[i].PopulateFrom(val)
+	}
+
+	result := CommandResult{
+		Format:    format.Format(outputFormat),
+		Filter:    options.Filter,
+		OrderBy:   options.OrderBy,
+		OutputAs:  toOutputType(options.OutputAs),
+		NameLimit: options.NameLimit,
+		Data:      data,
+	}
+
+	GenerateOutput(&result)
+	return nil
+}
+
+func (options *DeviceCreate) Execute(args []string) error {
+
+	dm := make(map[string]interface{})
+	if options.HostAndPort != "" {
+		dm["host_and_port"] = options.HostAndPort
+	} else if options.IPAddress != "" {
+		dm["ipv4_address"] = options.IPAddress
+	} else if options.MACAddress != "" {
+		dm["mac_address"] = strings.ToLower(options.MACAddress)
+	}
+	if options.DeviceType != "" {
+		dm["type"] = options.DeviceType
+	}
+
+	conn, err := NewConnection()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	descriptor, method, err := GetMethod("device-create")
+	if err != nil {
+		return err
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
+	defer cancel()
+
+	h := &RpcEventHandler{
+		Fields: map[string]map[string]interface{}{"voltha.Device": dm},
+	}
+	err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
+	if err != nil {
+		return err
+	} else if h.Status != nil && h.Status.Err() != nil {
+		return h.Status.Err()
+	}
+
+	resp, err := dynamic.AsDynamicMessage(h.Response)
+	if err != nil {
+		return err
+	}
+	fmt.Printf("%s\n", resp.GetFieldByName("id").(string))
+
+	return nil
+}
+
+func (options *DeviceDelete) Execute(args []string) error {
+
+	conn, err := NewConnection()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	descriptor, method, err := GetMethod("device-delete")
+	if err != nil {
+		return err
+	}
+
+	for _, i := range options.Args.Ids {
+
+		h := &RpcEventHandler{
+			Fields: map[string]map[string]interface{}{ParamNames[GlobalConfig.ApiVersion]["ID"]: {"id": i}},
+		}
+		ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
+		defer cancel()
+
+		err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
+		if err != nil {
+			fmt.Printf("Error while deleting '%s': %s\n", i, err)
+			continue
+		} else if h.Status != nil && h.Status.Err() != nil {
+			fmt.Printf("Error while deleting '%s': %s\n", i, h.Status.Err())
+			continue
+		}
+		fmt.Printf("%s\n", i)
+	}
+
+	return nil
+}
+
+func (options *DeviceEnable) Execute(args []string) error {
+	conn, err := NewConnection()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	descriptor, method, err := GetMethod("device-enable")
+	if err != nil {
+		return err
+	}
+
+	for _, i := range options.Args.Ids {
+		h := &RpcEventHandler{
+			Fields: map[string]map[string]interface{}{ParamNames[GlobalConfig.ApiVersion]["ID"]: {"id": i}},
+		}
+		ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
+		defer cancel()
+
+		err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
+		if err != nil {
+			fmt.Printf("Error while enabling '%s': %s\n", i, err)
+			continue
+		} else if h.Status != nil && h.Status.Err() != nil {
+			fmt.Printf("Error while enabling '%s': %s\n", i, h.Status.Err())
+			continue
+		}
+		fmt.Printf("%s\n", i)
+	}
+
+	return nil
+}
+
+func (options *DeviceDisable) Execute(args []string) error {
+	conn, err := NewConnection()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	descriptor, method, err := GetMethod("device-disable")
+	if err != nil {
+		return err
+	}
+
+	for _, i := range options.Args.Ids {
+		h := &RpcEventHandler{
+			Fields: map[string]map[string]interface{}{ParamNames[GlobalConfig.ApiVersion]["ID"]: {"id": i}},
+		}
+		ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
+		defer cancel()
+
+		err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
+		if err != nil {
+			fmt.Printf("Error while disabling '%s': %s\n", i, err)
+			continue
+		} else if h.Status != nil && h.Status.Err() != nil {
+			fmt.Printf("Error while disabling '%s': %s\n", i, h.Status.Err())
+			continue
+		}
+		fmt.Printf("%s\n", i)
+	}
+
+	return nil
+}
+
+func (options *DeviceReboot) Execute(args []string) error {
+	conn, err := NewConnection()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	descriptor, method, err := GetMethod("device-reboot")
+	if err != nil {
+		return err
+	}
+
+	for _, i := range options.Args.Ids {
+		h := &RpcEventHandler{
+			Fields: map[string]map[string]interface{}{ParamNames[GlobalConfig.ApiVersion]["ID"]: {"id": i}},
+		}
+		ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
+		defer cancel()
+
+		err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
+		if err != nil {
+			fmt.Printf("Error while rebooting '%s': %s\n", i, err)
+			continue
+		} else if h.Status != nil && h.Status.Err() != nil {
+			fmt.Printf("Error while rebooting '%s': %s\n", i, h.Status.Err())
+			continue
+		}
+		fmt.Printf("%s\n", i)
+	}
+
+	return nil
+}
+
+func (options *DevicePortList) Execute(args []string) error {
+
+	conn, err := NewConnection()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	descriptor, method, err := GetMethod("device-ports")
+	if err != nil {
+		return err
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
+	defer cancel()
+
+	h := &RpcEventHandler{
+		Fields: map[string]map[string]interface{}{ParamNames[GlobalConfig.ApiVersion]["ID"]: {"id": options.Args.Id}},
+	}
+	err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{}, h, h.GetParams)
+	if err != nil {
+		return err
+	}
+
+	if h.Status != nil && h.Status.Err() != nil {
+		return h.Status.Err()
+	}
+
+	d, err := dynamic.AsDynamicMessage(h.Response)
+	if err != nil {
+		return err
+	}
+
+	items, err := d.TryGetFieldByName("items")
+	if err != nil {
+		return err
+	}
+
+	outputFormat := CharReplacer.Replace(options.Format)
+	if outputFormat == "" {
+		outputFormat = DEFAULT_DEVICE_PORTS_FORMAT
+	}
+	if options.Quiet {
+		outputFormat = "{{.Id}}"
+	}
+
+	data := make([]model.DevicePort, len(items.([]interface{})))
+	for i, item := range items.([]interface{}) {
+		data[i].PopulateFrom(item.(*dynamic.Message))
+	}
+
+	result := CommandResult{
+		Format:    format.Format(outputFormat),
+		Filter:    options.Filter,
+		OrderBy:   options.OrderBy,
+		OutputAs:  toOutputType(options.OutputAs),
+		NameLimit: options.NameLimit,
+		Data:      data,
+	}
+
+	GenerateOutput(&result)
+	return nil
+}
+
+func (options *DeviceFlowList) Execute(args []string) error {
+	fl := &FlowList{}
+	fl.ListOutputOptions = options.ListOutputOptions
+	fl.Args.Id = string(options.Args.Id)
+	fl.Method = "device-flow-list"
+	return fl.Execute(args)
+}
+
+func (options *DeviceInspect) Execute(args []string) error {
+	if len(args) > 0 {
+		return fmt.Errorf("only a single argument 'DEVICE_ID' can be provided")
+	}
+
+	conn, err := NewConnection()
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	descriptor, method, err := GetMethod("device-inspect")
+	if err != nil {
+		return err
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), GlobalConfig.Grpc.Timeout)
+	defer cancel()
+
+	h := &RpcEventHandler{
+		Fields: map[string]map[string]interface{}{ParamNames[GlobalConfig.ApiVersion]["ID"]: {"id": options.Args.Id}},
+	}
+	err = grpcurl.InvokeRPC(ctx, descriptor, conn, method, []string{"Get-Depth: 2"}, h, h.GetParams)
+	if err != nil {
+		return err
+	} else if h.Status != nil && h.Status.Err() != nil {
+		return h.Status.Err()
+	}
+
+	d, err := dynamic.AsDynamicMessage(h.Response)
+	if err != nil {
+		return err
+	}
+
+	device := &model.Device{}
+	device.PopulateFrom(d)
+
+	outputFormat := CharReplacer.Replace(options.Format)
+	if outputFormat == "" {
+		outputFormat = DEFAULT_DEVICE_INSPECT_FORMAT
+	}
+	if options.Quiet {
+		outputFormat = "{{.Id}}"
+	}
+
+	result := CommandResult{
+		Format:    format.Format(outputFormat),
+		OutputAs:  toOutputType(options.OutputAs),
+		NameLimit: options.NameLimit,
+		Data:      device,
+	}
+	GenerateOutput(&result)
+	return nil
+}