diff --git a/validator/flags/BUILD.bazel b/validator/flags/BUILD.bazel
index 40044d6eb1..6e79b94f3b 100644
--- a/validator/flags/BUILD.bazel
+++ b/validator/flags/BUILD.bazel
@@ -2,7 +2,10 @@ load("@io_bazel_rules_go//go:def.bzl", "go_library")
 
 go_library(
     name = "go_default_library",
-    srcs = ["flags.go"],
+    srcs = [
+        "flags.go",
+        "interop.go",
+    ],
     importpath = "github.com/prysmaticlabs/prysm/validator/flags",
     visibility = ["//validator:__subpackages__"],
     deps = ["@in_gopkg_urfave_cli_v2//:go_default_library"],
diff --git a/validator/flags/flags.go b/validator/flags/flags.go
index f9f23fb2b6..c0716ccde2 100644
--- a/validator/flags/flags.go
+++ b/validator/flags/flags.go
@@ -21,6 +21,13 @@ var (
 		Name:  "tls-cert",
 		Usage: "Certificate for secure gRPC. Pass this and the tls-key flag in order to use gRPC securely.",
 	}
+	// UnencryptedKeysFlag specifies a file path of a JSON file of unencrypted validator keys; this should only
+	// be used for test networks.
+	UnencryptedKeysFlag = &cli.StringFlag{
+		Name:  "unencrypted-keys",
+		Usage: "Filepath to a JSON file of unencrypted validator keys for launching the validator client on test networks",
+		Value: "",
+	}
 	// KeyManager specifies the key manager to use.
 	KeyManager = &cli.StringFlag{
 		Name:  "keymanager",
diff --git a/validator/flags/interop.go b/validator/flags/interop.go
new file mode 100644
index 0000000000..a904db1eb9
--- /dev/null
+++ b/validator/flags/interop.go
@@ -0,0 +1,21 @@
+package flags
+
+import (
+	"gopkg.in/urfave/cli.v2"
+)
+
+// Flags defined for interoperability testing.
+var (
+	InteropStartIndex = &cli.Uint64Flag{
+		Name: "interop-start-index",
+		Usage: "The start index to deterministically generate validator keys when used in combination with " +
+			"--interop-num-validators. Example: --interop-start-index=5 --interop-num-validators=3 would generate " +
+			"keys from index 5 to 7.",
+	}
+	InteropNumValidators = &cli.Uint64Flag{
+		Name: "interop-num-validators",
+		Usage: "The number of validators to deterministically generate when used in combination with " +
+			"--interop-num-validators. Example: --interop-start-index=5 --interop-num-validators=3 would generate " +
+			"keys from index 5 to 7.",
+	}
+)
diff --git a/validator/main.go b/validator/main.go
index 8369f23a57..99fe64f87b 100644
--- a/validator/main.go
+++ b/validator/main.go
@@ -38,6 +38,9 @@ var appFlags = []cli.Flag{
 	flags.CertFlag,
 	flags.GraffitiFlag,
 	flags.DisablePenaltyRewardLogFlag,
+	flags.UnencryptedKeysFlag,
+	flags.InteropStartIndex,
+	flags.InteropNumValidators,
 	flags.GrpcMaxCallRecvMsgSizeFlag,
 	flags.GrpcRetriesFlag,
 	flags.GrpcHeadersFlag,
diff --git a/validator/node/node.go b/validator/node/node.go
index 18570f72f4..d77dea9009 100644
--- a/validator/node/node.go
+++ b/validator/node/node.go
@@ -198,9 +198,6 @@ func (s *ValidatorClient) registerClientService(ctx *cli.Context, keyManager key
 // selectKeyManager selects the key manager depending on the options provided by the user.
 func selectKeyManager(ctx *cli.Context) (keymanager.KeyManager, error) {
 	manager := strings.ToLower(ctx.String(flags.KeyManager.Name))
-	if manager == "" {
-		return nil, fmt.Errorf("please supply a keymanager with --keymanager")
-	}
 	opts := ctx.String(flags.KeyManagerOpts.Name)
 	if opts == "" {
 		opts = "{}"
@@ -212,6 +209,23 @@ func selectKeyManager(ctx *cli.Context) (keymanager.KeyManager, error) {
 		opts = string(fileopts)
 	}
 
+	if manager == "" {
+		// Attempt to work out keymanager from deprecated vars.
+		if unencryptedKeys := ctx.String(flags.UnencryptedKeysFlag.Name); unencryptedKeys != "" {
+			manager = "unencrypted"
+			opts = fmt.Sprintf(`{"path":%q}`, unencryptedKeys)
+			log.Warn(fmt.Sprintf("--unencrypted-keys flag is deprecated.  Please use --keymanager=unencrypted --keymanageropts='%s'", opts))
+		} else if numValidatorKeys := ctx.Uint64(flags.InteropNumValidators.Name); numValidatorKeys > 0 {
+			manager = "interop"
+			opts = fmt.Sprintf(`{"keys":%d,"offset":%d}`, numValidatorKeys, ctx.Uint64(flags.InteropStartIndex.Name))
+			log.Warn(fmt.Sprintf("--interop-num-validators and --interop-start-index flags are deprecated.  Please use --keymanager=interop --keymanageropts='%s'", opts))
+		}
+	}
+
+	if manager == "" {
+		return nil, fmt.Errorf("please supply a keymanager with --keymanager")
+	}
+
 	var km keymanager.KeyManager
 	var help string
 	var err error
diff --git a/validator/usage.go b/validator/usage.go
index 277f980a5f..54dd02ca55 100644
--- a/validator/usage.go
+++ b/validator/usage.go
@@ -78,6 +78,7 @@ var appHelpFlagGroups = []flagGroup{
 			flags.KeyManager,
 			flags.KeyManagerOpts,
 			flags.DisablePenaltyRewardLogFlag,
+			flags.UnencryptedKeysFlag,
 			flags.GraffitiFlag,
 			flags.GrpcMaxCallRecvMsgSizeFlag,
 			flags.GrpcRetriesFlag,
@@ -89,6 +90,13 @@ var appHelpFlagGroups = []flagGroup{
 		Name:  "features",
 		Flags: featureconfig.ActiveFlags(featureconfig.ValidatorFlags),
 	},
+	{
+		Name: "interop",
+		Flags: []cli.Flag{
+			flags.InteropNumValidators,
+			flags.InteropStartIndex,
+		},
+	},
 }
 
 func init() {