diff --git a/cmd/geth/accountcmd_test.go b/cmd/geth/accountcmd_test.go
index 66e3e02a4e..3ea22ccfab 100644
--- a/cmd/geth/accountcmd_test.go
+++ b/cmd/geth/accountcmd_test.go
@@ -134,7 +134,7 @@ Fatal: could not decrypt key with given passphrase
 func TestUnlockFlag(t *testing.T) {
 	datadir := tmpDatadirWithKeystore(t)
 	geth := runGeth(t,
-		"--datadir", datadir, "--nat", "none", "--nodiscover", "--dev",
+		"--datadir", datadir, "--nat", "none", "--nodiscover", "--maxpeers", "0", "--port", "0",
 		"--unlock", "f466859ead1932d743d622cb74fc058882e8648a",
 		"js", "testdata/empty.js")
 	geth.Expect(`
@@ -158,7 +158,7 @@ Passphrase: {{.InputLine "foobar"}}
 func TestUnlockFlagWrongPassword(t *testing.T) {
 	datadir := tmpDatadirWithKeystore(t)
 	geth := runGeth(t,
-		"--datadir", datadir, "--nat", "none", "--nodiscover", "--dev",
+		"--datadir", datadir, "--nat", "none", "--nodiscover", "--maxpeers", "0", "--port", "0",
 		"--unlock", "f466859ead1932d743d622cb74fc058882e8648a")
 	defer geth.ExpectExit()
 	geth.Expect(`
@@ -177,7 +177,7 @@ Fatal: Failed to unlock account f466859ead1932d743d622cb74fc058882e8648a (could
 func TestUnlockFlagMultiIndex(t *testing.T) {
 	datadir := tmpDatadirWithKeystore(t)
 	geth := runGeth(t,
-		"--datadir", datadir, "--nat", "none", "--nodiscover", "--dev",
+		"--datadir", datadir, "--nat", "none", "--nodiscover", "--maxpeers", "0", "--port", "0",
 		"--unlock", "0,2",
 		"js", "testdata/empty.js")
 	geth.Expect(`
@@ -204,7 +204,7 @@ Passphrase: {{.InputLine "foobar"}}
 func TestUnlockFlagPasswordFile(t *testing.T) {
 	datadir := tmpDatadirWithKeystore(t)
 	geth := runGeth(t,
-		"--datadir", datadir, "--nat", "none", "--nodiscover", "--dev",
+		"--datadir", datadir, "--nat", "none", "--nodiscover", "--maxpeers", "0", "--port", "0",
 		"--password", "testdata/passwords.txt", "--unlock", "0,2",
 		"js", "testdata/empty.js")
 	geth.ExpectExit()
@@ -224,7 +224,7 @@ func TestUnlockFlagPasswordFile(t *testing.T) {
 func TestUnlockFlagPasswordFileWrongPassword(t *testing.T) {
 	datadir := tmpDatadirWithKeystore(t)
 	geth := runGeth(t,
-		"--datadir", datadir, "--nat", "none", "--nodiscover", "--dev",
+		"--datadir", datadir, "--nat", "none", "--nodiscover", "--maxpeers", "0", "--port", "0",
 		"--password", "testdata/wrong-passwords.txt", "--unlock", "0,2")
 	defer geth.ExpectExit()
 	geth.Expect(`
@@ -235,7 +235,7 @@ Fatal: Failed to unlock account 0 (could not decrypt key with given passphrase)
 func TestUnlockFlagAmbiguous(t *testing.T) {
 	store := filepath.Join("..", "..", "accounts", "keystore", "testdata", "dupes")
 	geth := runGeth(t,
-		"--keystore", store, "--nat", "none", "--nodiscover", "--dev",
+		"--keystore", store, "--nat", "none", "--nodiscover", "--maxpeers", "0", "--port", "0",
 		"--unlock", "f466859ead1932d743d622cb74fc058882e8648a",
 		"js", "testdata/empty.js")
 	defer geth.ExpectExit()
@@ -273,7 +273,7 @@ In order to avoid this warning, you need to remove the following duplicate key f
 func TestUnlockFlagAmbiguousWrongPassword(t *testing.T) {
 	store := filepath.Join("..", "..", "accounts", "keystore", "testdata", "dupes")
 	geth := runGeth(t,
-		"--keystore", store, "--nat", "none", "--nodiscover", "--dev",
+		"--keystore", store, "--nat", "none", "--nodiscover", "--maxpeers", "0", "--port", "0",
 		"--unlock", "f466859ead1932d743d622cb74fc058882e8648a")
 	defer geth.ExpectExit()
 
diff --git a/cmd/geth/main.go b/cmd/geth/main.go
index 018fa8b71c..8bd27b5c6a 100644
--- a/cmd/geth/main.go
+++ b/cmd/geth/main.go
@@ -100,6 +100,7 @@ var (
 		utils.NodeKeyFileFlag,
 		utils.NodeKeyHexFlag,
 		utils.DeveloperFlag,
+		utils.DeveloperPeriodFlag,
 		utils.TestnetFlag,
 		utils.RinkebyFlag,
 		utils.VMEnableDebugFlag,
diff --git a/cmd/geth/usage.go b/cmd/geth/usage.go
index 7e2038f660..5bb2255f3b 100644
--- a/cmd/geth/usage.go
+++ b/cmd/geth/usage.go
@@ -72,7 +72,6 @@ var AppHelpFlagGroups = []flagGroup{
 			utils.NetworkIdFlag,
 			utils.TestnetFlag,
 			utils.RinkebyFlag,
-			utils.DeveloperFlag,
 			utils.SyncModeFlag,
 			utils.EthStatsURLFlag,
 			utils.IdentityFlag,
@@ -81,6 +80,12 @@ var AppHelpFlagGroups = []flagGroup{
 			utils.LightKDFFlag,
 		},
 	},
+	{Name: "DEVELOPER CHAIN",
+		Flags: []cli.Flag{
+			utils.DeveloperFlag,
+			utils.DeveloperPeriodFlag,
+		},
+	},
 	{
 		Name: "ETHASH",
 		Flags: []cli.Flag{
diff --git a/cmd/utils/flags.go b/cmd/utils/flags.go
index 5317c80ae5..3af625a6ac 100644
--- a/cmd/utils/flags.go
+++ b/cmd/utils/flags.go
@@ -139,7 +139,11 @@ var (
 	}
 	DeveloperFlag = cli.BoolFlag{
 		Name:  "dev",
-		Usage: "Developer mode: pre-configured private network with several debugging flags",
+		Usage: "Ephemeral proof-of-authority network with a pre-funded developer account, mining enabled",
+	}
+	DeveloperPeriodFlag = cli.IntFlag{
+		Name:  "dev.period",
+		Usage: "Block period to use in developer mode (0 = mine only if transaction pending)",
 	}
 	IdentityFlag = cli.StringFlag{
 		Name:  "identity",
@@ -995,7 +999,7 @@ func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *eth.Config) {
 		}
 		log.Info("Created developer account", "address", faucet.Address)
 
-		cfg.Genesis = core.DefaultDeveloperGenesisBlock(faucet.Address)
+		cfg.Genesis = core.DefaultDeveloperGenesisBlock(uint64(ctx.GlobalInt(DeveloperPeriodFlag.Name)), faucet.Address)
 		if !ctx.GlobalIsSet(GasPriceFlag.Name) {
 			cfg.GasPrice = big.NewInt(1)
 		}
diff --git a/consensus/clique/clique.go b/consensus/clique/clique.go
index ae9f91582b..6892d83906 100644
--- a/consensus/clique/clique.go
+++ b/consensus/clique/clique.go
@@ -126,10 +126,10 @@ var (
 	// errUnauthorized is returned if a header is signed by a non-authorized entity.
 	errUnauthorized = errors.New("unauthorized")
 
-	// errEmptyInstantBlock is returned if an empty block is attempted to be sealed
+	// errWaitTransactions is returned if an empty block is attempted to be sealed
 	// on an instant chain (0 second period). It's important to refuse these as the
 	// block reward is zero, so an empty block just bloats the chain... fast.
-	errEmptyInstantBlock = errors.New("empty instant block")
+	errWaitTransactions = errors.New("waiting for transactions")
 )
 
 // SignerFn is a signer callback function to request a hash to be signed by a
@@ -603,7 +603,7 @@ func (c *Clique) Seal(chain consensus.ChainReader, block *types.Block, stop <-ch
 	}
 	// For 0-period chains, refuse to seal empty blocks (no reward but would spin sealing)
 	if c.config.Period == 0 && len(block.Transactions()) == 0 {
-		return nil, errEmptyInstantBlock
+		return nil, errWaitTransactions
 	}
 	// Don't hold the signer fields for the entire sealing procedure
 	c.lock.RLock()
diff --git a/console/console_test.go b/console/console_test.go
index 8ac499bd12..0bc3d436e5 100644
--- a/console/console_test.go
+++ b/console/console_test.go
@@ -94,7 +94,7 @@ func newTester(t *testing.T, confOverride func(*eth.Config)) *tester {
 		t.Fatalf("failed to create node: %v", err)
 	}
 	ethConf := &eth.Config{
-		Genesis:   core.DevGenesisBlock(),
+		Genesis:   core.DefaultDeveloperGenesisBlock(15, common.Address{}),
 		Etherbase: common.HexToAddress(testAddress),
 		PowTest:   true,
 	}
diff --git a/core/genesis.go b/core/genesis.go
index ee99da5686..01ae8e9088 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -344,9 +344,14 @@ func DefaultRinkebyGenesisBlock() *Genesis {
 
 // DefaultDeveloperGenesisBlock returns the 'geth --dev' genesis block. Note, this
 // must be seeded with the
-func DefaultDeveloperGenesisBlock(faucet common.Address) *Genesis {
+func DefaultDeveloperGenesisBlock(period uint64, faucet common.Address) *Genesis {
+	// Override the default period to the user requested one
+	config := *params.AllCliqueProtocolChanges
+	config.Clique.Period = period
+
+	// Assemble and return the genesis with the precompiles and faucet pre-funded
 	return &Genesis{
-		Config:     params.AllCliqueProtocolChanges,
+		Config:     &config,
 		ExtraData:  append(append(make([]byte, 32), faucet[:]...), make([]byte, 65)...),
 		GasLimit:   4712388,
 		Difficulty: big.NewInt(1),
@@ -359,7 +364,7 @@ func DefaultDeveloperGenesisBlock(faucet common.Address) *Genesis {
 			common.Address{6}: GenesisAccount{Balance: big.NewInt(1)}, // ECAdd
 			common.Address{7}: GenesisAccount{Balance: big.NewInt(1)}, // ECScalarMul
 			common.Address{8}: GenesisAccount{Balance: big.NewInt(1)}, // ECPairing
-			faucet:            GenesisAccount{Balance: new(big.Int).Sub(new(big.Int).Lsh(big.NewInt(1), 256), big.NewInt(1))},
+			faucet:            GenesisAccount{Balance: new(big.Int).Sub(new(big.Int).Lsh(big.NewInt(1), 256), big.NewInt(8))},
 		},
 	}
 }