diff --git a/book.go b/book.go
index 81a307b9..c2e8668f 100644
--- a/book.go
+++ b/book.go
@@ -22,6 +22,7 @@ type book struct {
 	Vars        map[string]interface{}   `yaml:"vars,omitempty"`
 	Steps       []map[string]interface{} `yaml:"steps,omitempty"`
 	Debug       bool                     `yaml:"debug,omitempty"`
+	path        string
 	httpRunners map[string]*httpRunner
 	dbRunners   map[string]*dbRunner
 	t           *testing.T
@@ -68,6 +69,7 @@ func LoadBook(path string) (*book, error) {
 		_ = f.Close()
 		return nil, err
 	}
+	bk.path = path
 	if err := f.Close(); err != nil {
 		return nil, err
 	}
diff --git a/include.go b/include.go
new file mode 100644
index 00000000..db793bf6
--- /dev/null
+++ b/include.go
@@ -0,0 +1,52 @@
+package runn
+
+import (
+	"context"
+	"path/filepath"
+)
+
+const includeRunnerKey = "include"
+
+type includeRunner struct {
+	operator *operator
+}
+
+func newIncludeRunner(o *operator) (*includeRunner, error) {
+	return &includeRunner{
+		operator: o,
+	}, nil
+}
+
+func (rnr *includeRunner) Run(ctx context.Context, path string) error {
+	oo, err := rnr.operator.newNestedOperator(Book(filepath.Join(rnr.operator.root, path)))
+	if err != nil {
+		return err
+	}
+	if err := oo.Run(ctx); err != nil {
+		return err
+	}
+	rnr.operator.store.steps = append(rnr.operator.store.steps, map[string]interface{}{
+		"steps": oo.store.steps,
+	})
+	return nil
+}
+
+func (o *operator) newNestedOperator(opts ...Option) (*operator, error) {
+	for k, r := range o.httpRunners {
+		opts = append(opts, HTTPRunner(k, r.endpoint.String(), r.client))
+	}
+	for k, r := range o.dbRunners {
+		opts = append(opts, DBRunner(k, r.client))
+	}
+	for k, v := range o.store.vars {
+		opts = append(opts, Var(k, v))
+	}
+	opts = append(opts, Var("parent", o.store.steps))
+	opts = append(opts, Debug(o.debug))
+	oo, err := New(opts...)
+	if err != nil {
+		return nil, err
+	}
+	oo.t = o.t
+	return oo, nil
+}
diff --git a/include_test.go b/include_test.go
new file mode 100644
index 00000000..10ba9b00
--- /dev/null
+++ b/include_test.go
@@ -0,0 +1,49 @@
+package runn
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"testing"
+)
+
+func TestIncludeRunnerRun(t *testing.T) {
+	tests := []struct {
+		book string
+		want int
+	}{
+		{"testdata/book/db.yml", 8},
+	}
+	ctx := context.Background()
+	for _, tt := range tests {
+		db, err := os.CreateTemp("", "tmp")
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer os.Remove(db.Name())
+		o, err := New(Runner("db", fmt.Sprintf("sqlite://%s", db.Name())))
+		if err != nil {
+			t.Fatal(err)
+		}
+		r, err := newIncludeRunner(o)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if err := r.Run(ctx, tt.book); err != nil {
+			t.Fatal(err)
+		}
+
+		{
+			got := len(r.operator.store.steps)
+			if want := 1; got != want {
+				t.Errorf("got %v\nwant %v", got, want)
+			}
+		}
+		{
+			got := len(r.operator.store.steps[0]["steps"].([]map[string]interface{}))
+			if got != tt.want {
+				t.Errorf("got %v\nwant %v", got, tt.want)
+			}
+		}
+	}
+}
diff --git a/operator.go b/operator.go
index 7043fd98..7745f8f5 100644
--- a/operator.go
+++ b/operator.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"os"
+	"path/filepath"
 	"regexp"
 	"strconv"
 	"strings"
@@ -17,15 +18,17 @@ import (
 var expandRe = regexp.MustCompile(`"?{{\s*([^}]+)\s*}}"?`)
 
 type step struct {
-	httpRunner  *httpRunner
-	httpRequest map[string]interface{}
-	dbRunner    *dbRunner
-	dbQuery     map[string]interface{}
-	testRunner  *testRunner
-	testCond    string
-	dumpRunner  *dumpRunner
-	dumpCond    string
-	debug       bool
+	httpRunner    *httpRunner
+	httpRequest   map[string]interface{}
+	dbRunner      *dbRunner
+	dbQuery       map[string]interface{}
+	testRunner    *testRunner
+	testCond      string
+	dumpRunner    *dumpRunner
+	dumpCond      string
+	includeRunner *includeRunner
+	includePath   string
+	debug         bool
 }
 
 type store struct {
@@ -40,6 +43,7 @@ type operator struct {
 	store       store
 	desc        string
 	debug       bool
+	root        string
 	t           *testing.T
 }
 
@@ -50,6 +54,7 @@ func New(opts ...Option) (*operator, error) {
 			return nil, err
 		}
 	}
+
 	o := &operator{
 		httpRunners: map[string]*httpRunner{},
 		dbRunners:   map[string]*dbRunner{},
@@ -62,12 +67,20 @@ func New(opts ...Option) (*operator, error) {
 		t:     bk.t,
 	}
 
+	if bk.path != "" {
+		o.root = filepath.Dir(bk.path)
+	} else {
+		wd, err := os.Getwd()
+		if err != nil {
+			return nil, err
+		}
+		o.root = wd
+	}
+
 	for k, v := range bk.Runners {
 		switch {
-		case k == testRunnerKey:
-			return nil, fmt.Errorf("runners[%s] is reserved as test runner", testRunnerKey)
-		case k == dumpRunnerKey:
-			return nil, fmt.Errorf("runners[%s] is reserved as dump runner", dumpRunnerKey)
+		case k == includeRunnerKey || k == testRunnerKey || k == dumpRunnerKey:
+			return nil, fmt.Errorf("runner name '%s' is reserved for built-in runner", k)
 		case strings.Index(v, "https://") == 0 || strings.Index(v, "http://") == 0:
 			hc, err := newHTTPRunner(k, v, o)
 			if err != nil {
@@ -135,6 +148,19 @@ func (o *operator) AppendStep(s map[string]interface{}) error {
 			step.dumpCond = vv
 			continue
 		}
+		if k == includeRunnerKey {
+			ir, err := newIncludeRunner(o)
+			if err != nil {
+				return err
+			}
+			step.includeRunner = ir
+			vv, ok := v.(string)
+			if !ok {
+				return fmt.Errorf("invalid include path: %v", v)
+			}
+			step.includePath = vv
+			continue
+		}
 		h, ok := o.httpRunners[k]
 		if ok {
 			step.httpRunner = h
@@ -221,14 +247,21 @@ func (o *operator) run(ctx context.Context) error {
 				_, _ = fmt.Fprintf(os.Stderr, "Run '%s' on steps[%d]\n", testRunnerKey, i)
 			}
 			if err := s.testRunner.Run(ctx, s.testCond); err != nil {
-				return fmt.Errorf("test failed on steps[%d]: %s", i, s.testCond)
+				return fmt.Errorf("test failed on steps[%d]: %v", i, err)
 			}
 		case s.dumpRunner != nil && s.dumpCond != "":
 			if o.debug {
 				_, _ = fmt.Fprintf(os.Stderr, "Run '%s' on steps[%d]\n", dumpRunnerKey, i)
 			}
 			if err := s.dumpRunner.Run(ctx, s.dumpCond); err != nil {
-				return fmt.Errorf("dump failed on steps[%d]: %s", i, s.dumpCond)
+				return fmt.Errorf("dump failed on steps[%d]: %v", i, err)
+			}
+		case s.includeRunner != nil && s.includePath != "":
+			if o.debug {
+				_, _ = fmt.Fprintf(os.Stderr, "Run '%s' on steps[%d]\n", includeRunnerKey, i)
+			}
+			if err := s.includeRunner.Run(ctx, s.includePath); err != nil {
+				return fmt.Errorf("include failed on steps[%d]: %v", i, err)
 			}
 		default:
 			return fmt.Errorf("invalid steps[%d]: %v", i, s)
diff --git a/operator_test.go b/operator_test.go
index 39ffce29..05c909a8 100644
--- a/operator_test.go
+++ b/operator_test.go
@@ -159,8 +159,8 @@ func TestLoad(t *testing.T) {
 		path string
 		want int
 	}{
-		{"testdata/book/*", 3},
-		{"testdata/**/*", 3},
+		{"testdata/book/*", 4},
+		{"testdata/**/*", 4},
 	}
 	for _, tt := range tests {
 		ops, err := Load(tt.path, Runner("req", "https://api.github.com"), Runner("db", "sqlite://path/to/test.db"))
diff --git a/option.go b/option.go
index 1ff365d2..c6436b5d 100644
--- a/option.go
+++ b/option.go
@@ -29,6 +29,7 @@ func Book(path string) Option {
 		}
 		bk.Steps = loaded.Steps
 		bk.Debug = loaded.Debug
+		bk.path = loaded.path
 		return nil
 	}
 }
diff --git a/testdata/book/db.yml b/testdata/book/db.yml
index cdb683bf..b3873e0d 100644
--- a/testdata/book/db.yml
+++ b/testdata/book/db.yml
@@ -1,34 +1,22 @@
 desc: Test using SQLite3
 steps:
   -
-    db:
-      query: |
-        CREATE TABLE users (
-          id INTEGER PRIMARY KEY AUTOINCREMENT,
-          username TEXT UNIQUE NOT NULL,
-          password TEXT NOT NULL,
-          email TEXT UNIQUE NOT NULL,
-          created NUMERIC NOT NULL,
-          updated NUMERIC
-        )
-  -
-    db:
-      query: INSERT INTO users (username, password, email, created) VALUES ('alice', 'passw0rd', 'alice@example.com', datetime('2017-12-05'))
+    include: initdb.yml
   -
     db:
       query: SELECT * FROM users;
   -
-    test: 'steps[2].rows[0].username == "alice"'
+    test: 'steps[1].rows[0].username == "alice"'
   -
     db:
-      query: INSERT INTO users (username, password, email, created) VALUES ('bob', 'passw0rd', 'bob@example.com', datetime('2022-02-22'))
+      query: INSERT INTO users (username, password, email, created) VALUES ('charlie', 'passw0rd', 'charlie@example.com', datetime('2022-02-22'))
   -
     db:
-      query: SELECT * FROM users WHERE id = {{ steps[4].last_insert_id }}
+      query: SELECT * FROM users WHERE id = {{ steps[3].last_insert_id }}
   -
-    test: 'steps[5].rows[0].username == "bob"'
+    test: 'steps[4].rows[0].username == "charlie"'
   -
     db:
       query: SELECT COUNT(*) AS c FROM users
   -
-    test: 'steps[7].rows[0].c == 2'
+    test: 'steps[6].rows[0].c == 3'
diff --git a/testdata/book/initdb.yml b/testdata/book/initdb.yml
new file mode 100644
index 00000000..9237f1df
--- /dev/null
+++ b/testdata/book/initdb.yml
@@ -0,0 +1,19 @@
+desc: Initialize SQLite3
+steps:
+  -
+    db:
+      query: |
+        CREATE TABLE users (
+          id INTEGER PRIMARY KEY AUTOINCREMENT,
+          username TEXT UNIQUE NOT NULL,
+          password TEXT NOT NULL,
+          email TEXT UNIQUE NOT NULL,
+          created NUMERIC NOT NULL,
+          updated NUMERIC
+        )
+  -
+    db:
+      query: INSERT INTO users (username, password, email, created) VALUES ('alice', 'passw0rd', 'alice@example.com', datetime('2017-12-05'))
+  -
+    db:
+      query: INSERT INTO users (username, password, email, created) VALUES ('bob', 'passw0rd', 'bob@example.com', datetime('2022-02-22'))