diff --git a/blocks/vote.go b/blocks/vote.go
index 041657096..94ee854af 100644
--- a/blocks/vote.go
+++ b/blocks/vote.go
@@ -2,6 +2,7 @@ package blocks
 
 import (
 	"errors"
+	"fmt"
 	"io"
 
 	. "github.com/tendermint/tendermint/binary"
@@ -56,3 +57,20 @@ func (v *Vote) GetSignature() Signature {
 func (v *Vote) SetSignature(sig Signature) {
 	v.Signature = sig
 }
+
+func (v *Vote) String() string {
+	blockHash := v.BlockHash
+	if len(v.BlockHash) == 0 {
+		blockHash = make([]byte, 6) // for printing
+	}
+	switch v.Type {
+	case VoteTypeBare:
+		return fmt.Sprintf("Vote{%v/%v:%X:%v}", v.Height, v.Round, blockHash, v.SignerId)
+	case VoteTypePrecommit:
+		return fmt.Sprintf("Precommit{%v/%v:%X:%v}", v.Height, v.Round, blockHash, v.SignerId)
+	case VoteTypeCommit:
+		return fmt.Sprintf("Commit{%v/%v:%X:%v}", v.Height, v.Round, v.BlockHash[:6], v.SignerId)
+	default:
+		panic("Unknown vote type")
+	}
+}
diff --git a/common/bit_array.go b/common/bit_array.go
index d771c4c39..1070018fa 100644
--- a/common/bit_array.go
+++ b/common/bit_array.go
@@ -4,6 +4,7 @@ import (
 	"io"
 	"math"
 	"math/rand"
+	"strings"
 
 	. "github.com/tendermint/tendermint/binary"
 )
@@ -153,3 +154,33 @@ func (bA BitArray) PickRarest(counts []int) (rarest int, ok bool) {
 	}
 	return
 }
+
+func (bA BitArray) String() string {
+	return bA.StringWithIndent("")
+}
+
+func (bA BitArray) StringWithIndent(indent string) string {
+	lines := []string{}
+	bits := ""
+	for i := 0; i < len(bA)*64; i++ {
+		if bA.GetIndex(uint(i)) {
+			bits += "X"
+		} else {
+			bits += "_"
+		}
+		if i%100 == 99 {
+			lines = append(lines, bits)
+			bits = ""
+		}
+		if i%10 == 9 {
+			bits += " "
+		}
+		if i%50 == 49 {
+			bits += " "
+		}
+	}
+	if len(bits) > 0 {
+		lines = append(lines, bits)
+	}
+	return strings.Join(lines, indent)
+}
diff --git a/consensus/state.go b/consensus/state.go
index a590b9213..df75d0aa0 100644
--- a/consensus/state.go
+++ b/consensus/state.go
@@ -142,9 +142,9 @@ func (cs *ConsensusState) setupRound(round uint16) {
 	cs.ProposalPOL = nil
 	cs.ProposalPOLPartSet = nil
 	cs.Votes = NewVoteSet(cs.Height, round, VoteTypeBare, validators)
-	cs.Votes.AddVotesFromCommits(cs.Commits)
+	cs.Votes.AddFromCommits(cs.Commits)
 	cs.Precommits = NewVoteSet(cs.Height, round, VoteTypePrecommit, validators)
-	cs.Precommits.AddVotesFromCommits(cs.Commits)
+	cs.Precommits.AddFromCommits(cs.Commits)
 }
 
 func (cs *ConsensusState) SetStep(step byte) {
@@ -289,15 +289,15 @@ func (cs *ConsensusState) AddVote(vote *Vote) (added bool, err error) {
 	switch vote.Type {
 	case VoteTypeBare:
 		// Votes checks for height+round match.
-		return cs.Votes.AddVote(vote)
+		return cs.Votes.Add(vote)
 	case VoteTypePrecommit:
 		// Precommits checks for height+round match.
-		return cs.Precommits.AddVote(vote)
+		return cs.Precommits.Add(vote)
 	case VoteTypeCommit:
 		// Commits checks for height match.
-		cs.Votes.AddVote(vote)
-		cs.Precommits.AddVote(vote)
-		return cs.Commits.AddVote(vote)
+		cs.Votes.Add(vote)
+		cs.Precommits.Add(vote)
+		return cs.Commits.Add(vote)
 	default:
 		panic("Unknown vote type")
 	}
diff --git a/consensus/vote_set.go b/consensus/vote_set.go
index 8dd2b8855..62501fa1d 100644
--- a/consensus/vote_set.go
+++ b/consensus/vote_set.go
@@ -2,7 +2,8 @@ package consensus
 
 import (
 	"bytes"
-
+	"fmt"
+	"strings"
 	"sync"
 	"time"
 
@@ -50,7 +51,7 @@ func NewVoteSet(height uint32, round uint16, type_ byte, vset *ValidatorSet) *Vo
 
 // True if added, false if not.
 // Returns ErrVote[UnexpectedPhase|InvalidAccount|InvalidSignature|InvalidBlockHash|ConflictingSignature]
-func (vs *VoteSet) AddVote(vote *Vote) (bool, error) {
+func (vs *VoteSet) Add(vote *Vote) (bool, error) {
 	vs.mtx.Lock()
 	defer vs.mtx.Unlock()
 
@@ -109,7 +110,7 @@ func (vs *VoteSet) addVote(vote *Vote) (bool, error) {
 }
 
 // Assumes that commits VoteSet is valid.
-func (vs *VoteSet) AddVotesFromCommits(commits *VoteSet) {
+func (vs *VoteSet) AddFromCommits(commits *VoteSet) {
 	commitVotes := commits.AllVotes()
 	for _, commit := range commitVotes {
 		if commit.Round < vs.round {
@@ -177,3 +178,26 @@ func (vs *VoteSet) MakePOL() *POL {
 	}
 	return pol
 }
+
+func (vs *VoteSet) String() string {
+	return vs.StringWithIndent("")
+}
+
+func (vs *VoteSet) StringWithIndent(indent string) string {
+	vs.mtx.Lock()
+	defer vs.mtx.Unlock()
+
+	voteStrings := make([]string, len(vs.votes))
+	for _, vote := range vs.votes {
+		voteStrings[vote.SignerId] = vote.String()
+	}
+	return fmt.Sprintf(`VoteSet{
+%s  H:%v R:%v T:%v
+%s  %v
+%s  %v
+%s}`,
+		indent, vs.height, vs.round, vs.type_,
+		indent, strings.Join(voteStrings, "\n"+indent+"  "),
+		indent, vs.votesBitArray,
+		indent)
+}
diff --git a/consensus/vote_set_test.go b/consensus/vote_set_test.go
index 3d378138f..c8db9e670 100644
--- a/consensus/vote_set_test.go
+++ b/consensus/vote_set_test.go
@@ -1,6 +1,7 @@
 package consensus
 
 import (
+	. "github.com/tendermint/tendermint/blocks"
 	. "github.com/tendermint/tendermint/state"
 
 	"testing"
@@ -15,8 +16,33 @@ func makeValidator(id uint64, votingPower uint64) (*Validator, *PrivAccount) {
 	}, privAccount
 }
 
+func makeVoteSet(numValidators int, votingPower uint64) (*VoteSet, *ValidatorSet, []*PrivAccount) {
+	vals := make([]*Validator, numValidators)
+	privAccounts := make([]*PrivAccount, numValidators)
+	for i := 0; i < numValidators; i++ {
+		val, privAccount := makeValidator(uint64(i), votingPower)
+		vals[i] = val
+		privAccounts[i] = privAccount
+	}
+	valSet := NewValidatorSet(vals)
+	return NewVoteSet(0, 0, VoteTypeBare, valSet), valSet, privAccounts
+}
+
 func TestAddVote(t *testing.T) {
-	// XXX
+	voteSet, valSet, privAccounts := makeVoteSet(10, 1)
+	vote := &Vote{Height: 0, Round: 0, Type: VoteTypeBare, BlockHash: nil}
+
+	t.Logf(">> %v", voteSet)
+	t.Logf(">> %v", valSet)
+	t.Logf(">> %v", privAccounts)
+
+	privAccounts[0].Sign(vote)
+	voteSet.Add(vote)
+
+	t.Logf(">> %v", voteSet)
+	t.Logf(">> %v", valSet)
+	t.Logf(">> %v", privAccounts)
+
 }
 
 func Test2_3Majority(t *testing.T) {
diff --git a/state/account.go b/state/account.go
index d099155d0..ec4450a14 100644
--- a/state/account.go
+++ b/state/account.go
@@ -39,6 +39,9 @@ func (account Account) VerifyBytes(msg []byte, sig Signature) bool {
 	if sig.SignerId != account.Id {
 		panic("account.id doesn't match sig.signerid")
 	}
+	if len(sig.Bytes) == 0 {
+		panic("signature is empty")
+	}
 	v1 := &crypto.Verify{
 		Message:   msg,
 		PubKey:    account.PubKey,
@@ -57,7 +60,7 @@ func (account Account) Verify(o Signable) bool {
 }
 
 func (account Account) String() string {
-	return fmt.Sprintf("Account{%v:%X}", account.Id, account.PubKey)
+	return fmt.Sprintf("Account{%v:%X}", account.Id, account.PubKey[:6])
 }
 
 //-----------------------------------------------------------------------------