diff --git a/protocol/config/consensus.go b/protocol/config/consensus.go
index 1cabaa87..bfc70901 100644
--- a/protocol/config/consensus.go
+++ b/protocol/config/consensus.go
@@ -84,11 +84,6 @@ type ConsensusParams struct {
 	// a way of making the spender subsidize the cost of storing this transaction.
 	MinTxnFee uint64
 
-	// EnableFeePooling specifies that the sum of the fees in a
-	// group must exceed one MinTxnFee per Txn, rather than check that
-	// each Txn has a MinFee.
-	EnableFeePooling bool
-
 	// EnableAppCostPooling specifies that the sum of fees for application calls
 	// in a group is checked against the sum of the budget for application calls,
 	// rather than check each individual app call is within the budget.
@@ -562,6 +557,10 @@ type ConsensusParams struct {
 	// specify the current app. This parameter can be removed and assumed true
 	// after the first consensus release in which it is set true.
 	AllowZeroLocalAppRef bool
+
+	// LoadTracking enables header values that track Load that grows/shrinks
+	// when blocks are more/less than half full.
+	LoadTracking bool
 }
 
 // ProposerPayoutRules puts several related consensus parameters in one place. The same
@@ -1090,7 +1089,6 @@ func initConsensusProtocols() {
 	// "reachability" between accounts and creatables, so we
 	// retain 4 x 4 as worst case.
 
-	v28.EnableFeePooling = true
 	v28.EnableKeyregCoherencyCheck = true
 
 	Consensus[protocol.ConsensusV28] = v28
@@ -1367,10 +1365,10 @@ func initConsensusProtocols() {
 	vFuture.ApprovedUpgrades = map[protocol.ConsensusVersion]uint64{}
 
 	vFuture.LogicSigVersion = 13 // When moving this to a release, put a new higher LogicSigVersion here
-
 	vFuture.AppSizeUpdates = true
 	vFuture.AllowZeroLocalAppRef = true
 	vFuture.EnforceAuthAddrSenderDiff = true
+	vFuture.LoadTracking = true
 
 	Consensus[protocol.ConsensusFuture] = vFuture
 
diff --git a/types/block.go b/types/block.go
index 5143c0f6..584b8a70 100644
--- a/types/block.go
+++ b/types/block.go
@@ -114,6 +114,16 @@ type BlockHeader struct {
 	// ParticipationUpdates contains the information needed to mark
 	// certain accounts offline because their participation keys expired
 	ParticipationUpdates
+
+	// Load is the degree to which a block is full. Currently, it is based on
+	// the number of bytes in the final block, compared to the maximum allowed.
+	// It is expressed as a fixed-point integer with 6 digits of precision.  So,
+	// 1,000,000 is a completely full block.
+	Load Micros `codec:"ld"`
+
+	// CongestionTax fee required, beyond the MinFee, for "normal"
+	// transactions in this block.
+	CongestionTax Micros `codec:"ct"`
 }
 
 // TxnCommitments represents the commitments computed from the transactions in the block.
@@ -337,3 +347,7 @@ const (
 	// DeleteAction indicates that the value for a particular key should be deleted
 	DeleteAction DeltaAction = 3
 )
+
+// Micros represents millionths of something. It's a fixed-point number with 6
+// digits of precision.
+type Micros uint64