diff --git a/pkg/labels/labels.go b/pkg/labels/labels.go
new file mode 100644
index 000000000..8025feb67
--- /dev/null
+++ b/pkg/labels/labels.go
@@ -0,0 +1,153 @@
+package labels
+
+import (
+	"bytes"
+	"sort"
+	"strconv"
+	"strings"
+
+	"github.com/cespare/xxhash"
+)
+
+const sep = '\xff'
+
+// Well-known label names used by Prometheus components.
+const (
+	MetricName = "__name__"
+	AlertName  = "alertname"
+)
+
+// Label is a key/value pair of strings.
+type Label struct {
+	Name, Value string
+}
+
+// Labels is a sorted set of labels. Order has to be guaranteed upon
+// instantiation.
+type Labels []Label
+
+func (ls Labels) Len() int           { return len(ls) }
+func (ls Labels) Swap(i, j int)      { ls[i], ls[j] = ls[j], ls[i] }
+func (ls Labels) Less(i, j int) bool { return ls[i].Name < ls[j].Name }
+
+func (ls Labels) String() string {
+	var b bytes.Buffer
+
+	b.WriteByte('{')
+	for i, l := range ls {
+		if i > 0 {
+			b.WriteByte(',')
+		}
+		b.WriteString(l.Name)
+		b.WriteByte('=')
+		b.WriteString(strconv.Quote(l.Value))
+	}
+	b.WriteByte('}')
+
+	return b.String()
+}
+
+// Hash returns a hash value for the label set.
+func (ls Labels) Hash() uint64 {
+	b := make([]byte, 0, 1024)
+
+	for _, v := range ls {
+		b = append(b, v.Name...)
+		b = append(b, sep)
+		b = append(b, v.Value...)
+		b = append(b, sep)
+	}
+	return xxhash.Sum64(b)
+}
+
+// Get returns the value for the label with the given name.
+// Returns an empty string if the label doesn't exist.
+func (ls Labels) Get(name string) string {
+	for _, l := range ls {
+		if l.Name == name {
+			return l.Value
+		}
+	}
+	return ""
+}
+
+// Equals returns whether the two label sets are equal.
+func (ls Labels) Equals(o Labels) bool {
+	if len(ls) != len(o) {
+		return false
+	}
+	for i, l := range ls {
+		if l.Name != o[i].Name || l.Value != o[i].Value {
+			return false
+		}
+	}
+	return true
+}
+
+// Map returns a string map of the labels.
+func (ls Labels) Map() map[string]string {
+	m := make(map[string]string, len(ls))
+	for _, l := range ls {
+		m[l.Name] = l.Value
+	}
+	return m
+}
+
+// New returns a sorted Labels from the given labels.
+// The caller has to guarantee that all label names are unique.
+func New(ls ...Label) Labels {
+	set := make(Labels, 0, len(ls))
+	for _, l := range ls {
+		set = append(set, l)
+	}
+	sort.Sort(set)
+
+	return set
+}
+
+// FromMap returns new sorted Labels from the given map.
+func FromMap(m map[string]string) Labels {
+	l := make([]Label, 0, len(m))
+	for k, v := range m {
+		l = append(l, Label{Name: k, Value: v})
+	}
+	return New(l...)
+}
+
+// FromStrings creates new labels from pairs of strings.
+func FromStrings(ss ...string) Labels {
+	if len(ss)%2 != 0 {
+		panic("invalid number of strings")
+	}
+	var res Labels
+	for i := 0; i < len(ss); i += 2 {
+		res = append(res, Label{Name: ss[i], Value: ss[i+1]})
+	}
+
+	sort.Sort(res)
+	return res
+}
+
+// Compare compares the two label sets.
+// The result will be 0 if a==b, <0 if a < b, and >0 if a > b.
+func Compare(a, b Labels) int {
+	l := len(a)
+	if len(b) < l {
+		l = len(b)
+	}
+
+	for i := 0; i < l; i++ {
+		if d := strings.Compare(a[i].Name, b[i].Name); d != 0 {
+			return d
+		}
+		if d := strings.Compare(a[i].Value, b[i].Value); d != 0 {
+			return d
+		}
+	}
+	// If all labels so far were in common, the set with fewer labels comes first.
+	return len(a) - len(b)
+}
+
+type LabelsBuilder struct {
+	base Labels
+}
diff --git a/promql/ast.go b/promql/ast.go
index e24e0cb21..a765094d6 100644
--- a/promql/ast.go
+++ b/promql/ast.go
@@ -17,9 +17,11 @@ import (
 	"fmt"
 	"regexp"
 	"time"
+	"unsafe"
 
 	"github.com/fabxc/tsdb"
-	"github.com/fabxc/tsdb/labels"
+	tsdbLabels "github.com/fabxc/tsdb/labels"
+	"github.com/prometheus/prometheus/pkg/labels"
 )
 
 // Node is a generic interface for all nodes in an AST.
@@ -368,31 +370,39 @@ func NewLabelMatcher(t MatchType, n, v string) (*LabelMatcher, error) {
 	return m, nil
 }
 
+func toTSDBLabels(l labels.Labels) tsdbLabels.Labels {
+	return *(*tsdbLabels.Labels)(unsafe.Pointer(&l))
+}
+
+func toLabels(l tsdbLabels.Labels) labels.Labels {
+	return *(*labels.Labels)(unsafe.Pointer(&l))
+}
+
 func (m *LabelMatcher) String() string {
 	return fmt.Sprintf("%s%s%q", m.Name, m.Type, m.Value)
 }
 
-func (m *LabelMatcher) matcher() labels.Matcher {
+func (m *LabelMatcher) matcher() tsdbLabels.Matcher {
 	switch m.Type {
 	case MatchEqual:
-		return labels.NewEqualMatcher(m.Name, m.Value)
+		return tsdbLabels.NewEqualMatcher(m.Name, m.Value)
 
 	case MatchNotEqual:
-		return labels.Not(labels.NewEqualMatcher(m.Name, m.Value))
+		return tsdbLabels.Not(tsdbLabels.NewEqualMatcher(m.Name, m.Value))
 
 	case MatchRegexp:
-		res, err := labels.NewRegexpMatcher(m.Name, m.Value)
+		res, err := tsdbLabels.NewRegexpMatcher(m.Name, m.Value)
 		if err != nil {
 			panic(err)
 		}
 		return res
 
 	case MatchNotRegexp:
-		res, err := labels.NewRegexpMatcher(m.Name, m.Value)
+		res, err := tsdbLabels.NewRegexpMatcher(m.Name, m.Value)
 		if err != nil {
 			panic(err)
 		}
-		return labels.Not(res)
+		return tsdbLabels.Not(res)
 	}
 	panic("promql.LabelMatcher.matcher: invalid matcher type")
 }
diff --git a/promql/engine.go b/promql/engine.go
index e566176b0..14bec5799 100644
--- a/promql/engine.go
+++ b/promql/engine.go
@@ -23,8 +23,9 @@ import (
 	"time"
 
 	"github.com/fabxc/tsdb"
-	"github.com/fabxc/tsdb/labels"
+	tsdbLabels "github.com/fabxc/tsdb/labels"
 	"github.com/prometheus/common/log"
+	"github.com/prometheus/prometheus/pkg/labels"
 	"golang.org/x/net/context"
 
 	"github.com/prometheus/prometheus/util/stats"
@@ -555,7 +556,7 @@ func (ng *Engine) populateIterators(ctx context.Context, s *EvalStmt) (tsdb.Quer
 	Inspect(s.Expr, func(node Node) bool {
 		switch n := node.(type) {
 		case *VectorSelector:
-			sel := make(labels.Selector, 0, len(n.LabelMatchers))
+			sel := make(tsdbLabels.Selector, 0, len(n.LabelMatchers))
 			for _, m := range n.LabelMatchers {
 				sel = append(sel, m.matcher())
 			}
@@ -569,7 +570,7 @@ func (ng *Engine) populateIterators(ctx context.Context, s *EvalStmt) (tsdb.Quer
 				n.iterators = append(n.iterators, it)
 			}
 		case *MatrixSelector:
-			sel := make(labels.Selector, 0, len(n.LabelMatchers))
+			sel := make(tsdbLabels.Selector, 0, len(n.LabelMatchers))
 			for _, m := range n.LabelMatchers {
 				sel = append(sel, m.matcher())
 			}
@@ -805,7 +806,7 @@ func (ev *evaluator) VectorSelector(node *VectorSelector) Vector {
 		}
 
 		vec = append(vec, Sample{
-			Metric: node.series[i].Labels(),
+			Metric: toLabels(node.series[i].Labels()),
 			Point:  Point{V: v, T: ev.Timestamp},
 		})
 	}
@@ -823,7 +824,7 @@ func (ev *evaluator) MatrixSelector(node *MatrixSelector) Matrix {
 
 	for i, it := range node.iterators {
 		ss := Series{
-			Metric: node.series[i].Labels(),
+			Metric: toLabels(node.series[i].Labels()),
 			Points: make([]Point, 0, 16),
 		}
 
diff --git a/promql/functions.go b/promql/functions.go
index b8167cd8a..97d4a520c 100644
--- a/promql/functions.go
+++ b/promql/functions.go
@@ -20,8 +20,8 @@ import (
 	"strconv"
 	"time"
 
-	"github.com/fabxc/tsdb/labels"
 	"github.com/prometheus/common/model"
+	"github.com/prometheus/prometheus/pkg/labels"
 )
 
 // Function represents a function of the expression language and is
diff --git a/promql/parse.go b/promql/parse.go
index 09bb761a7..525efd2ec 100644
--- a/promql/parse.go
+++ b/promql/parse.go
@@ -21,9 +21,9 @@ import (
 	"strings"
 	"time"
 
-	"github.com/fabxc/tsdb/labels"
 	"github.com/prometheus/common/log"
 	"github.com/prometheus/common/model"
+	"github.com/prometheus/prometheus/pkg/labels"
 
 	"github.com/prometheus/prometheus/util/strutil"
 )
diff --git a/promql/printer_test.go b/promql/printer_test.go
index 1f64e2aee..7407f717c 100644
--- a/promql/printer_test.go
+++ b/promql/printer_test.go
@@ -17,7 +17,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/fabxc/tsdb/labels"
+	"github.com/prometheus/prometheus/pkg/labels"
 )
 
 func TestStatementString(t *testing.T) {
diff --git a/promql/quantile.go b/promql/quantile.go
index 7761316ab..c7c905460 100644
--- a/promql/quantile.go
+++ b/promql/quantile.go
@@ -17,8 +17,8 @@ import (
 	"math"
 	"sort"
 
-	"github.com/fabxc/tsdb/labels"
 	"github.com/prometheus/common/model"
+	"github.com/prometheus/prometheus/pkg/labels"
 )
 
 // Helpers to calculate quantiles.
diff --git a/promql/test.go b/promql/test.go
index ccaa6550b..fbb02e84e 100644
--- a/promql/test.go
+++ b/promql/test.go
@@ -22,8 +22,8 @@ import (
 	"strings"
 	"time"
 
-	"github.com/fabxc/tsdb/labels"
 	"github.com/prometheus/common/model"
+	"github.com/prometheus/prometheus/pkg/labels"
 	"golang.org/x/net/context"
 
 	"github.com/prometheus/prometheus/storage"