diff --git a/.gitignore b/.gitignore
index 6529e9498..997aa63a7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,4 @@
-.tools/
\ No newline at end of file
+.tools/
+.idea/
+*.iml
+*.so
diff --git a/api/core/core.go b/api/core/core.go
index dce685f2c..0fa0bd002 100644
--- a/api/core/core.go
+++ b/api/core/core.go
@@ -17,6 +17,9 @@ package core
 import (
 	"context"
 	"fmt"
+	"strconv"
+
+	"google.golang.org/grpc/codes"
 
 	"github.com/open-telemetry/opentelemetry-go/api/unit"
 )
@@ -132,6 +135,12 @@ const (
 	DELETE
 )
 
+var (
+	// INVALID_SPAN_CONTEXT is meant for internal use to return invalid span context during error
+	// conditions.
+	INVALID_SPAN_CONTEXT = SpanContext{}
+)
+
 func (sc SpanContext) HasTraceID() bool {
 	return sc.TraceIDHigh != 0 || sc.TraceIDLow != 0
 }
@@ -191,3 +200,44 @@ func (m Measurement) With(id ScopeID) Measurement {
 	m.ScopeID = id
 	return m
 }
+
+func GrpcCodeToString(s codes.Code) string {
+	switch c := s; c {
+	case codes.OK:
+		return "OK"
+	case codes.Canceled:
+		return "CANCELLED"
+	case codes.Unknown:
+		return "UNKNOWN"
+	case codes.InvalidArgument:
+		return "INVALID_ARGUMENT"
+	case codes.DeadlineExceeded:
+		return "DEADLINE_EXCEEDED"
+	case codes.NotFound:
+		return "NOT_FOUND"
+	case codes.AlreadyExists:
+		return "ALREADY_EXISTS"
+	case codes.PermissionDenied:
+		return "PERMISSION_DENIED"
+	case codes.ResourceExhausted:
+		return "RESOURCE_EXHAUSTED"
+	case codes.FailedPrecondition:
+		return "FAILED_PRECONDITION"
+	case codes.Aborted:
+		return "ABORTED"
+	case codes.OutOfRange:
+		return "OUT_OF_RANGE"
+	case codes.Unimplemented:
+		return "UNIMPLEMENTED"
+	case codes.Internal:
+		return "INTERNAL"
+	case codes.Unavailable:
+		return "UNAVAILABLE"
+	case codes.DataLoss:
+		return "DATA_LOSS"
+	case codes.Unauthenticated:
+		return "UNAUTHENTICATED"
+	default:
+		return "STATUS_" + strconv.FormatInt(int64(c), 10)
+	}
+}
diff --git a/api/trace/api.go b/api/trace/api.go
index 7fbdaa8b0..3f09a0a55 100644
--- a/api/trace/api.go
+++ b/api/trace/api.go
@@ -18,6 +18,8 @@ import (
 	"context"
 	"time"
 
+	"google.golang.org/grpc/codes"
+
 	"github.com/open-telemetry/opentelemetry-go/api/core"
 	"github.com/open-telemetry/opentelemetry-go/api/log"
 	"github.com/open-telemetry/opentelemetry-go/api/scope"
@@ -27,7 +29,7 @@ import (
 
 type (
 	Tracer interface {
-		Start(context.Context, string, ...Option) (context.Context, Span)
+		Start(context.Context, string, ...SpanOption) (context.Context, Span)
 
 		WithSpan(
 			ctx context.Context,
@@ -58,17 +60,29 @@ type (
 		Tracer() Tracer
 
 		Finish()
+
+		// IsRecordingEvents returns true is the span is active and recording events is enabled.
+		IsRecordingEvents() bool
+
+		// SpancContext returns span context of the span. Return SpanContext is usable
+		// even after the span is finished.
+		SpanContext() core.SpanContext
+
+		SetStatus(codes.Code)
 	}
 
 	Injector interface {
 		Inject(core.SpanContext, tag.Map)
 	}
 
-	Option struct {
-		attribute  core.KeyValue
-		attributes []core.KeyValue
-		startTime  time.Time
-		reference  Reference
+	// SpanOption apply changes to SpanOptions.
+	SpanOption func(*SpanOptions)
+
+	SpanOptions struct {
+		attributes  []core.KeyValue
+		startTime   time.Time
+		reference   Reference
+		recordEvent bool
 	}
 
 	Reference struct {
@@ -95,7 +109,7 @@ func SetGlobalTracer(t Tracer) {
 	global.Store(t)
 }
 
-func Start(ctx context.Context, name string, opts ...Option) (context.Context, Span) {
+func Start(ctx context.Context, name string, opts ...SpanOption) (context.Context, Span) {
 	return GlobalTracer().Start(ctx, name, opts...)
 }
 
@@ -121,38 +135,38 @@ func Inject(ctx context.Context, injector Injector) {
 	span.Tracer().Inject(ctx, span, injector)
 }
 
-func WithStartTime(t time.Time) Option {
-	return Option{
-		startTime: t,
+func WithStartTime(t time.Time) SpanOption {
+	return func(o *SpanOptions) {
+		o.startTime = t
 	}
 }
 
-func WithAttributes(attrs ...core.KeyValue) Option {
-	return Option{
-		attributes: attrs,
+func WithAttributes(attrs ...core.KeyValue) SpanOption {
+	return func(o *SpanOptions) {
+		o.attributes = attrs
 	}
 }
 
-func WithAttribute(attr core.KeyValue) Option {
-	return Option{
-		attribute: attr,
+func WithRecordEvents() SpanOption {
+	return func(o *SpanOptions) {
+		o.recordEvent = true
 	}
 }
 
-func ChildOf(sc core.SpanContext) Option {
-	return Option{
-		reference: Reference{
+func ChildOf(sc core.SpanContext) SpanOption {
+	return func(o *SpanOptions) {
+		o.reference = Reference{
 			SpanContext:      sc,
 			RelationshipType: ChildOfRelationship,
-		},
+		}
 	}
 }
 
-func FollowsFrom(sc core.SpanContext) Option {
-	return Option{
-		reference: Reference{
+func FollowsFrom(sc core.SpanContext) SpanOption {
+	return func(o *SpanOptions) {
+		o.reference = Reference{
 			SpanContext:      sc,
 			RelationshipType: FollowsFromRelationship,
-		},
+		}
 	}
 }
diff --git a/api/trace/span.go b/api/trace/span.go
index b0b7083d6..45546b9a8 100644
--- a/api/trace/span.go
+++ b/api/trace/span.go
@@ -17,12 +17,44 @@ package trace
 import (
 	"context"
 
+	"google.golang.org/grpc/codes"
+
 	"github.com/open-telemetry/opentelemetry-go/api/core"
 	"github.com/open-telemetry/opentelemetry-go/api/log"
 	"github.com/open-telemetry/opentelemetry-go/api/stats"
 	"github.com/open-telemetry/opentelemetry-go/exporter/observer"
 )
 
+// SpancContext returns span context of the span. Return SpanContext is usable
+// even after the span is finished.
+func (sp *span) SpanContext() core.SpanContext {
+	if sp == nil {
+		return core.INVALID_SPAN_CONTEXT
+	}
+	return sp.spanContext
+}
+
+// IsRecordingEvents returns true is the span is active and recording events is enabled.
+func (sp *span) IsRecordingEvents() bool {
+	return false
+}
+
+// SetStatus sets the status of the span.
+func (sp *span) SetStatus(status codes.Code) {
+	if sp == nil {
+		return
+	}
+	sid := sp.ScopeID()
+
+	observer.Record(observer.Event{
+		Type:     observer.SET_STATUS,
+		Scope:    sid,
+		Sequence: sid.EventID,
+		Status:   status,
+	})
+	sp.status = status
+}
+
 func (sp *span) ScopeID() core.ScopeID {
 	if sp == nil {
 		return core.ScopeID{}
diff --git a/api/trace/trace.go b/api/trace/trace.go
index 597a314e9..aa4417eb8 100644
--- a/api/trace/trace.go
+++ b/api/trace/trace.go
@@ -19,7 +19,8 @@ import (
 	"math/rand"
 	"sync"
 	"sync/atomic"
-	"time"
+
+	"google.golang.org/grpc/codes"
 
 	"github.com/open-telemetry/opentelemetry-go/api/core"
 	"github.com/open-telemetry/opentelemetry-go/api/log"
@@ -35,6 +36,8 @@ type (
 		lock        sync.Mutex
 		eventID     core.EventID
 		finishOnce  sync.Once
+		recordEvent bool
+		status      codes.Code
 	}
 
 	tracer struct {
@@ -93,34 +96,21 @@ func (t *tracer) WithSpan(ctx context.Context, name string, body func(context.Co
 	return nil
 }
 
-func (t *tracer) Start(ctx context.Context, name string, opts ...Option) (context.Context, Span) {
+func (t *tracer) Start(ctx context.Context, name string, opts ...SpanOption) (context.Context, Span) {
 	var child core.SpanContext
 
 	child.SpanID = rand.Uint64()
 
-	var startTime time.Time
-	var attributes []core.KeyValue
-	var reference Reference
+	o := &SpanOptions{}
 
 	for _, opt := range opts {
-		if !opt.startTime.IsZero() {
-			startTime = opt.startTime
-		}
-		if len(opt.attributes) != 0 {
-			attributes = append(opt.attributes, attributes...)
-		}
-		if opt.attribute.Key != nil {
-			attributes = append(attributes, opt.attribute)
-		}
-		if opt.reference.HasTraceID() {
-			reference = opt.reference
-		}
+		opt(o)
 	}
 
 	var parentScope core.ScopeID
 
-	if reference.HasTraceID() {
-		parentScope = reference.Scope()
+	if o.reference.HasTraceID() {
+		parentScope = o.reference.Scope()
 	} else {
 		parentScope = Active(ctx).ScopeID()
 	}
@@ -142,10 +132,11 @@ func (t *tracer) Start(ctx context.Context, name string, opts ...Option) (contex
 	span := &span{
 		spanContext: child,
 		tracer:      t,
+		recordEvent: o.recordEvent,
 		eventID: observer.Record(observer.Event{
-			Time:    startTime,
+			Time:    o.startTime,
 			Type:    observer.START_SPAN,
-			Scope:   scope.New(childScope, attributes...).ScopeID(),
+			Scope:   scope.New(childScope, o.attributes...).ScopeID(),
 			Context: ctx,
 			Parent:  parentScope,
 			String:  name,
diff --git a/example/http/client/client.go b/example/http/client/client.go
index 23306752e..172b57242 100644
--- a/example/http/client/client.go
+++ b/example/http/client/client.go
@@ -24,6 +24,8 @@ import (
 	"github.com/open-telemetry/opentelemetry-go/api/trace"
 	"github.com/open-telemetry/opentelemetry-go/plugin/httptrace"
 
+	"google.golang.org/grpc/codes"
+
 	_ "github.com/open-telemetry/opentelemetry-go/exporter/loader"
 )
 
@@ -59,6 +61,7 @@ func main() {
 			}
 			body, err = ioutil.ReadAll(res.Body)
 			res.Body.Close()
+			trace.Active(ctx).SetStatus(codes.OK)
 
 			return err
 		})
diff --git a/exporter/observer/observer.go b/exporter/observer/observer.go
index cd4df24e7..2c5558357 100644
--- a/exporter/observer/observer.go
+++ b/exporter/observer/observer.go
@@ -20,6 +20,8 @@ import (
 	"sync/atomic"
 	"time"
 
+	"google.golang.org/grpc/codes"
+
 	"github.com/open-telemetry/opentelemetry-go/api/core"
 )
 
@@ -43,6 +45,7 @@ type (
 		Mutators   []core.Mutator  // SET_ATTRIBUTES
 		Arguments  []interface{}   // LOGF_EVENT
 		Recovered  interface{}     // FINISH_SPAN
+		Status     codes.Code      // SET_STATUS
 
 		// Values
 		String  string // START_SPAN, EVENT, ...
@@ -72,6 +75,7 @@ const (
 	NEW_METRIC
 	MODIFY_ATTR
 	RECORD_STATS
+	SET_STATUS
 )
 
 var (
diff --git a/exporter/reader/format/format.go b/exporter/reader/format/format.go
index 8bf8f9c9e..2d924de71 100644
--- a/exporter/reader/format/format.go
+++ b/exporter/reader/format/format.go
@@ -92,6 +92,10 @@ func AppendEvent(buf *strings.Builder, data reader.Event) {
 			})
 			buf.WriteString("}")
 		}
+	case reader.SET_STATUS:
+		buf.WriteString("set status ")
+		buf.WriteString(core.GrpcCodeToString(data.Status))
+
 	default:
 		buf.WriteString(fmt.Sprintf("WAT? %d", data.Type))
 	}
diff --git a/exporter/reader/reader.go b/exporter/reader/reader.go
index db48a1ff7..0686524bc 100644
--- a/exporter/reader/reader.go
+++ b/exporter/reader/reader.go
@@ -19,6 +19,8 @@ import (
 	"sync"
 	"time"
 
+	"google.golang.org/grpc/codes"
+
 	"github.com/open-telemetry/opentelemetry-go/api/core"
 	"github.com/open-telemetry/opentelemetry-go/api/metric"
 	"github.com/open-telemetry/opentelemetry-go/api/tag"
@@ -49,6 +51,7 @@ type (
 		Duration time.Duration
 		Name     string
 		Message  string
+		Status   codes.Code
 	}
 
 	Measurement struct {
@@ -75,6 +78,7 @@ type (
 		start       time.Time
 		startTags   tag.Map
 		spanContext core.SpanContext
+		status      codes.Code
 
 		*readerScope
 	}
@@ -106,6 +110,7 @@ const (
 	LOGF_EVENT
 	MODIFY_ATTR
 	RECORD_STATS
+	SET_STATUS
 )
 
 // NewReaderObserver returns an implementation that computes the
@@ -291,6 +296,15 @@ func (ro *readerObserver) Observe(event observer.Event) {
 			ro.addMeasurement(&read, event.Stat)
 		}
 
+	case observer.SET_STATUS:
+		read.Type = SET_STATUS
+		read.Status = event.Status
+		_, span := ro.readScope(event.Scope)
+		if span != nil {
+			span.status = event.Status
+			read.SpanContext = span.spanContext
+		}
+
 	default:
 		panic(fmt.Sprint("Unhandled case: ", event.Type))
 	}
diff --git a/go.mod b/go.mod
index 2ff6b9720..c7f5965d4 100644
--- a/go.mod
+++ b/go.mod
@@ -8,4 +8,5 @@ require (
 	github.com/onsi/ginkgo v1.8.0 // indirect
 	github.com/onsi/gomega v1.5.0 // indirect
 	golang.org/x/tools v0.0.0-20190521203540-521d6ed310dd
+	google.golang.org/grpc v1.21.1
 )
diff --git a/go.sum b/go.sum
index 884cd3c59..6833a5db3 100644
--- a/go.sum
+++ b/go.sum
@@ -1,13 +1,18 @@
+cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
 github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/OpenPeeDeeP/depguard v0.0.0-20180806142446-a69c782687b2 h1:HTOmFEEYrWi4MW5ZKUx6xfeyM10Sx3kQF65xiQJMPYA=
 github.com/OpenPeeDeeP/depguard v0.0.0-20180806142446-a69c782687b2/go.mod h1:7/4sitnI9YlQgTLLk734QlzXT8DuHVnAyztLplQjk+o=
 github.com/StackExchange/wmi v0.0.0-20180116203802-5d049714c4a6/go.mod h1:3eOhrUMpNV+6aFIbp5/iudMxNCF27Vw2OZgy4xEx0Fg=
+github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/fatih/color v1.6.0 h1:66qjqZk8kalYAvDRtM1AdAJQI0tj4Wrue3Eq3B3pmFU=
 github.com/fatih/color v1.6.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
+github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
+github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/go-critic/go-critic v0.0.0-20181204210945-1df300866540 h1:7CU1IXBpPvxpQ/NqJrpuMXMHAw+FB2vfqtRF8tgW9fw=
 github.com/go-critic/go-critic v0.0.0-20181204210945-1df300866540/go.mod h1:+sE8vrLDS2M0pZkBk0wy6+nLdKexVDrl/jBqQOTDThA=
@@ -43,9 +48,14 @@ github.com/gobwas/glob v0.2.3 h1:A4xDbljILXROh+kObIiy5kIaPYD8e96x1tgBhUI5J+Y=
 github.com/gobwas/glob v0.2.3/go.mod h1:d3Ez4x06l9bZtSvzIay5+Yzi0fmZzPgnTbPcKjJAkT8=
 github.com/gogo/protobuf v1.1.1 h1:72R+M5VuhED/KujmZVcIquuo8mBgX4oVda//DQb3PXo=
 github.com/gogo/protobuf v1.1.1/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7atdtwQ=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
 github.com/golang/mock v1.0.0 h1:HzcpUG60pfl43n9d2qbdi/3l1uKpAmxlfWEPWtV/QxM=
 github.com/golang/mock v1.0.0/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
+github.com/golang/mock v1.1.1 h1:G5FRp8JnTd7RQH5kemVNlMeyXQAztQ3mOWV95KxsXH8=
+github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
 github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
+github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golangci/check v0.0.0-20180506172741-cfe4005ccda2 h1:23T5iq8rbUYlhpt5DB4XJkc6BU31uODLD1o1gKvZmD0=
 github.com/golangci/check v0.0.0-20180506172741-cfe4005ccda2/go.mod h1:k9Qvh+8juN+UKMCS/3jFtGICgW8O96FVaZsaxdzDkR4=
@@ -83,6 +93,7 @@ github.com/golangci/unconvert v0.0.0-20180507085042-28b1c447d1f4 h1:zwtduBRr5SSW
 github.com/golangci/unconvert v0.0.0-20180507085042-28b1c447d1f4/go.mod h1:Izgrg8RkN3rCIMLGE9CyYmU9pY2Jer6DgANEnZ/L/cQ=
 github.com/google/go-cmp v0.2.0 h1:+dTQ8DZQJz0Mb/HjFlkptS1FeQ4cWSnN941F8aEG4SQ=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
+github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/gostaticanalysis/analysisutil v0.0.0-20190318220348-4088753ea4d3 h1:JVnpOZS+qxli+rgVl98ILOXVNbW+kb5wcxeGx8ShUIw=
 github.com/gostaticanalysis/analysisutil v0.0.0-20190318220348-4088753ea4d3/go.mod h1:eEOZF4jCKGi+aprrirO9e7WKB3beBRtWgqGunKl6pKE=
 github.com/hashicorp/hcl v0.0.0-20180404174102-ef8a98b0bbce h1:xdsDDbiBDQTKASoGEZ+pEmF1OnWuu8AQ9I8iNbHNeno=
@@ -170,15 +181,22 @@ github.com/valyala/fasthttp v1.2.0/go.mod h1:4vX61m6KN+xDduDNwXrhIAVZaZaZiQ1luJk
 github.com/valyala/quicktemplate v1.1.1/go.mod h1:EH+4AkTd43SvgIbQHYu59/cJyxDoOVRUAfrukLPuGJ4=
 github.com/valyala/tcplisten v0.0.0-20161114210144-ceec8f93295a/go.mod h1:v3UYOV9WzVtRmSR+PDvWpU/qWl4Wa5LApYYX4ZtKbio=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20190313024323-a1f597ede03a h1:YX8ljsm6wXlHZO+aRz9Exqr0evNhKRNe5K/gi+zKh4U=
 golang.org/x/crypto v0.0.0-20190313024323-a1f597ede03a/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/lint v0.0.0-20190313153728-d0100b6bd8b3/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc=
 golang.org/x/net v0.0.0-20170915142106-8351a756f30f/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
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@@ -186,11 +204,15 @@ golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJ
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@@ -198,10 +220,16 @@ golang.org/x/tools v0.0.0-20181117154741-2ddaf7f79a09/go.mod h1:n7NCudcB/nEzxVGm
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@@ -218,6 +246,7 @@ gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWD
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