diff --git a/README.md b/README.md
index 83310e5..67df853 100644
--- a/README.md
+++ b/README.md
@@ -278,7 +278,6 @@ implement:
 * TAR
 * S3
 * Mem buffering to disk/network
-* BasePath (where all paths are relative to a fixed basepath)
 
 # Filters
 
@@ -299,12 +298,20 @@ The `AddFilter` adds a new FilterFs before any existing filters.
 
 ## Available filters
 
-* NewReadonlyFilter() - provide a read only view of the source Fs
-* NewRegexpFilter(*regexp.Regexp) - provide a filtered view on file names, any
-file (not directory) NOT matching the passed regexp will be treated as
-non-existing
+# NewBasePathFs(Fs, path)
 
+The BasePathFs restricts all operations to a given path within an Fs.
+The given file name to the operations on this Fs will be prepended with
+the base path before calling the base Fs.
 
+# NewReadonlyFilter()
+
+provide a read only view of the source Fs
+
+# NewRegexpFilter(\*regexp.Regexp)
+
+provide a filtered view on file names, any file (not directory) NOT matching
+the passed regexp will be treated as non-existing
 
 # About the project
 
diff --git a/basepath.go b/basepath.go
new file mode 100644
index 0000000..87ce784
--- /dev/null
+++ b/basepath.go
@@ -0,0 +1,130 @@
+package afero
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+type BasePathFs struct {
+	base Fs
+	path string
+}
+
+// The BasePathFs restricts all operations to a given path within an Fs.
+// The given file name to the operations on this Fs will be prepended with
+// the base path before calling the base Fs.
+// Any file name (after filepath.Clean()) outside this base path will be
+// treated as non existing file.
+//
+// Note that it does not clean the error messages on return, so you may
+// reveal the real path on errors.
+func NewBasePathFs(base Fs, path string) FilterFs {
+	return &BasePathFs{base: base, path: filepath.Clean(path) + string(os.PathSeparator)}
+}
+
+func (b *BasePathFs) AddFilter(fs FilterFs) {
+	fs.SetSource(b.base)
+	b.base = fs
+}
+
+func (b *BasePathFs) SetSource(fs Fs) {
+	b.base = fs
+}
+
+// on a file outside the base path it returns the given file name and an error,
+// else the given file with the base path prepended
+func (b *BasePathFs) RealPath(name string) (path string, err error) {
+	path = filepath.Clean(filepath.Join(b.path, name))
+	if !strings.HasPrefix(path, b.path) {
+		return name, os.ErrNotExist
+	}
+	return path, nil
+}
+
+func (b *BasePathFs) Chtimes(name string, atime, mtime time.Time) (err error) {
+	if name, err = b.RealPath(name); err != nil {
+		return &os.PathError{"chtimes", name, err}
+	}
+	return b.base.Chtimes(name, atime, mtime)
+}
+
+func (b *BasePathFs) Chmod(name string, mode os.FileMode) (err error) {
+	if name, err = b.RealPath(name); err != nil {
+		return &os.PathError{"chmod", name, err}
+	}
+	return b.base.Chmod(name, mode)
+}
+
+func (b *BasePathFs) Name() string {
+	return "BasePathFs"
+}
+
+func (b *BasePathFs) Stat(name string) (fi os.FileInfo, err error) {
+	if name, err = b.RealPath(name); err != nil {
+		return nil, &os.PathError{"stat", name, err}
+	}
+	return b.base.Stat(name)
+}
+
+func (b *BasePathFs) Rename(oldname, newname string) (err error) {
+	if oldname, err = b.RealPath(oldname); err != nil {
+		return &os.PathError{"rename", oldname, err}
+	}
+	if newname, err = b.RealPath(newname); err != nil {
+		return &os.PathError{"rename", newname, err}
+	}
+	return b.base.Rename(oldname, newname)
+}
+
+func (b *BasePathFs) RemoveAll(name string) (err error) {
+	if name, err = b.RealPath(name); err != nil {
+		return &os.PathError{"remove_all", name, err}
+	}
+	return b.base.RemoveAll(name)
+}
+
+func (b *BasePathFs) Remove(name string) (err error) {
+	if name, err = b.RealPath(name); err != nil {
+		return &os.PathError{"remove", name, err}
+	}
+	return b.base.Remove(name)
+}
+
+func (b *BasePathFs) OpenFile(name string, flag int, mode os.FileMode) (f File, err error) {
+	if name, err = b.RealPath(name); err != nil {
+		return nil, &os.PathError{"openfile", name, err}
+	}
+	return b.base.OpenFile(name, flag, mode)
+}
+
+func (b *BasePathFs) Open(name string) (f File, err error) {
+	if name, err = b.RealPath(name); err != nil {
+		return nil, &os.PathError{"open", name, err}
+	}
+	return b.base.Open(name)
+}
+
+func (b *BasePathFs) Mkdir(name string, mode os.FileMode) (err error) {
+	if name, err = b.RealPath(name); err != nil {
+		return &os.PathError{"mkdir", name, err}
+	}
+	return b.base.Mkdir(name, mode)
+}
+
+func (b *BasePathFs) MkdirAll(name string, mode os.FileMode) (err error) {
+	if name, err = b.RealPath(name); err != nil {
+		return &os.PathError{"mkdir", name, err}
+	}
+	return b.base.MkdirAll(name, mode)
+}
+
+func (b *BasePathFs) Create(name string) (f File, err error) {
+	if name, err = b.RealPath(name); err != nil {
+		return nil, &os.PathError{"create", name, err}
+	}
+	return b.base.Create(name)
+}
+
+// vim: ts=4 sw=4 noexpandtab nolist syn=go
diff --git a/basepath_test.go b/basepath_test.go
new file mode 100644
index 0000000..f45567e
--- /dev/null
+++ b/basepath_test.go
@@ -0,0 +1,19 @@
+package afero
+
+import (
+    "testing"
+)
+
+func TestBasePath(t *testing.T) {
+    baseFs := &MemMapFs{}
+    baseFs.MkdirAll("/base/path/tmp", 0777)
+    bp := NewBasePathFs(baseFs, "/base/path")
+
+    if _, err := bp.Create("/tmp/foo"); err != nil {
+        t.Errorf("Failed to set real path")
+    }
+
+    if fh, err := bp.Create("../tmp/bar"); err == nil {
+        t.Errorf("succeeded in creating %s ...", fh.Name())
+    }
+}