diff --git a/pantheon/src/main/java/tech/pegasys/pantheon/util/BlockImporter.java b/pantheon/src/main/java/tech/pegasys/pantheon/util/BlockImporter.java
index 38dfc47502..0cc6c38455 100644
--- a/pantheon/src/main/java/tech/pegasys/pantheon/util/BlockImporter.java
+++ b/pantheon/src/main/java/tech/pegasys/pantheon/util/BlockImporter.java
@@ -12,15 +12,15 @@
  */
 package tech.pegasys.pantheon.util;
 
+import static java.util.concurrent.TimeUnit.SECONDS;
 import static org.apache.logging.log4j.LogManager.getLogger;
 
 import tech.pegasys.pantheon.controller.PantheonController;
 import tech.pegasys.pantheon.ethereum.ProtocolContext;
-import tech.pegasys.pantheon.ethereum.blockcreation.AbstractBlockCreator;
-import tech.pegasys.pantheon.ethereum.blockcreation.BlockMiner;
 import tech.pegasys.pantheon.ethereum.chain.MutableBlockchain;
 import tech.pegasys.pantheon.ethereum.core.Block;
 import tech.pegasys.pantheon.ethereum.core.BlockHeader;
+import tech.pegasys.pantheon.ethereum.core.Transaction;
 import tech.pegasys.pantheon.ethereum.mainnet.BlockHeaderValidator;
 import tech.pegasys.pantheon.ethereum.mainnet.HeaderValidationMode;
 import tech.pegasys.pantheon.ethereum.mainnet.ProtocolSchedule;
@@ -31,6 +31,12 @@ import tech.pegasys.pantheon.util.uint.UInt256;
 
 import java.io.IOException;
 import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Semaphore;
 
 import com.google.common.base.MoreObjects;
 import org.apache.logging.log4j.Logger;
@@ -38,6 +44,12 @@ import org.apache.logging.log4j.Logger;
 /** Pantheon Block Import Util. */
 public class BlockImporter {
   private static final Logger LOG = getLogger();
+
+  private final Semaphore blockBacklog = new Semaphore(2);
+
+  private final ExecutorService validationExecutor = Executors.newCachedThreadPool();
+  private final ExecutorService importExecutor = Executors.newSingleThreadExecutor();
+
   /**
    * Imports blocks that are stored as concatenated RLP sections in the given file into Pantheon's
    * block storage.
@@ -45,15 +57,15 @@ public class BlockImporter {
    * @param blocks Path to the file containing the blocks
    * @param pantheonController the PantheonController that defines blockchain behavior
    * @param <C> the consensus context type
-   * @param <M> the type of miner being used within the executing pantheon
    * @return the import result
    * @throws IOException On Failure
    */
-  public <C, M extends BlockMiner<C, ? extends AbstractBlockCreator<C>>>
-      BlockImporter.ImportResult importBlockchain(
-          final Path blocks, final PantheonController<C> pantheonController) throws IOException {
+  public <C> BlockImporter.ImportResult importBlockchain(
+      final Path blocks, final PantheonController<C> pantheonController) throws IOException {
     final ProtocolSchedule<C> protocolSchedule = pantheonController.getProtocolSchedule();
     final ProtocolContext<C> context = pantheonController.getProtocolContext();
+    final MutableBlockchain blockchain = context.getBlockchain();
+    int count = 0;
 
     try (final RawBlockIterator iterator =
         new RawBlockIterator(
@@ -61,9 +73,8 @@ public class BlockImporter {
             rlp ->
                 BlockHeader.readFrom(
                     rlp, ScheduleBasedBlockHashFunction.create(protocolSchedule)))) {
-      final MutableBlockchain blockchain = context.getBlockchain();
-      int count = 1;
       BlockHeader previousHeader = null;
+      CompletableFuture<Void> previousBlockFuture = null;
       while (iterator.hasNext()) {
         final Block block = iterator.next();
         final BlockHeader header = block.getHeader();
@@ -80,31 +91,102 @@ public class BlockImporter {
           previousHeader = lookupPreviousHeader(blockchain, header);
         }
         final ProtocolSpec<C> protocolSpec = protocolSchedule.getByBlockNumber(header.getNumber());
-        final BlockHeaderValidator<C> blockHeaderValidator = protocolSpec.getBlockHeaderValidator();
-        final boolean validHeader =
-            blockHeaderValidator.validateHeader(
-                header, previousHeader, context, HeaderValidationMode.FULL);
-        if (!validHeader) {
-          throw new IllegalStateException(
-              "Invalid header at block number " + header.getNumber() + ".");
+        final BlockHeader lastHeader = previousHeader;
+
+        final CompletableFuture<Void> validationFuture =
+            CompletableFuture.runAsync(
+                () -> validateBlock(protocolSpec, context, lastHeader, header), validationExecutor);
+
+        final CompletableFuture<Void> extractingFuture =
+            CompletableFuture.runAsync(() -> extractSignatures(block));
+
+        final CompletableFuture<Void> calculationFutures;
+        if (previousBlockFuture == null) {
+          calculationFutures = extractingFuture;
+        } else {
+          calculationFutures = CompletableFuture.allOf(extractingFuture, previousBlockFuture);
         }
-        final tech.pegasys.pantheon.ethereum.core.BlockImporter<C> blockImporter =
-            protocolSpec.getBlockImporter();
-        final boolean blockImported =
-            blockImporter.importBlock(context, block, HeaderValidationMode.NONE);
-        if (!blockImported) {
-          throw new IllegalStateException(
-              "Invalid block at block number " + header.getNumber() + ".");
+
+        try {
+          blockBacklog.acquire();
+        } catch (final InterruptedException e) {
+          LOG.error("Interrupted adding to backlog.", e);
+          break;
         }
+        previousBlockFuture =
+            validationFuture.runAfterBothAsync(
+                calculationFutures,
+                () -> evaluateBlock(context, block, header, protocolSpec),
+                importExecutor);
+
         ++count;
         previousHeader = header;
       }
+      if (previousBlockFuture != null) {
+        previousBlockFuture.join();
+      }
       return new BlockImporter.ImportResult(blockchain.getChainHead().getTotalDifficulty(), count);
     } finally {
+      validationExecutor.shutdownNow();
+      try {
+        validationExecutor.awaitTermination(5, SECONDS);
+      } catch (final Exception e) {
+        LOG.error("Error shutting down validatorExecutor.", e);
+      }
+      importExecutor.shutdownNow();
+      try {
+        importExecutor.awaitTermination(5, SECONDS);
+      } catch (final Exception e) {
+        LOG.error("Error shutting down importExecutor", e);
+      }
       pantheonController.close();
     }
   }
 
+  private void extractSignatures(final Block block) {
+    final List<CompletableFuture<Void>> futures =
+        new ArrayList<>(block.getBody().getTransactions().size());
+    for (final Transaction tx : block.getBody().getTransactions()) {
+      futures.add(CompletableFuture.runAsync(tx::getSender, validationExecutor));
+    }
+    for (final CompletableFuture<Void> future : futures) {
+      future.join();
+    }
+  }
+
+  private <C> void validateBlock(
+      final ProtocolSpec<C> protocolSpec,
+      final ProtocolContext<C> context,
+      final BlockHeader previousHeader,
+      final BlockHeader header) {
+    final BlockHeaderValidator<C> blockHeaderValidator = protocolSpec.getBlockHeaderValidator();
+    final boolean validHeader =
+        blockHeaderValidator.validateHeader(
+            header, previousHeader, context, HeaderValidationMode.FULL);
+    if (!validHeader) {
+      throw new IllegalStateException("Invalid header at block number " + header.getNumber() + ".");
+    }
+  }
+
+  private <C> void evaluateBlock(
+      final ProtocolContext<C> context,
+      final Block block,
+      final BlockHeader header,
+      final ProtocolSpec<C> protocolSpec) {
+    try {
+      final tech.pegasys.pantheon.ethereum.core.BlockImporter<C> blockImporter =
+          protocolSpec.getBlockImporter();
+      final boolean blockImported =
+          blockImporter.importBlock(context, block, HeaderValidationMode.NONE);
+      if (!blockImported) {
+        throw new IllegalStateException(
+            "Invalid block at block number " + header.getNumber() + ".");
+      }
+    } finally {
+      blockBacklog.release();
+    }
+  }
+
   private BlockHeader lookupPreviousHeader(
       final MutableBlockchain blockchain, final BlockHeader header) {
     return blockchain
@@ -121,7 +203,7 @@ public class BlockImporter {
 
     public final UInt256 td;
 
-    public final int count;
+    final int count;
 
     ImportResult(final UInt256 td, final int count) {
       this.td = td;
diff --git a/pantheon/src/test/java/tech/pegasys/pantheon/util/BlockImporterTest.java b/pantheon/src/test/java/tech/pegasys/pantheon/util/BlockImporterTest.java
index 2bc49c2415..262f54df61 100644
--- a/pantheon/src/test/java/tech/pegasys/pantheon/util/BlockImporterTest.java
+++ b/pantheon/src/test/java/tech/pegasys/pantheon/util/BlockImporterTest.java
@@ -60,7 +60,8 @@ public final class BlockImporterTest {
             PrivacyParameters.noPrivacy());
     final BlockImporter.ImportResult result =
         blockImporter.importBlockchain(source, targetController);
-    assertThat(result.count).isEqualTo(1000);
+    // Don't count the Genesis block
+    assertThat(result.count).isEqualTo(999);
     assertThat(result.td).isEqualTo(UInt256.of(21991996248790L));
   }
 
@@ -93,6 +94,7 @@ public final class BlockImporterTest {
             PrivacyParameters.noPrivacy());
     final BlockImporter.ImportResult result = blockImporter.importBlockchain(source, controller);
 
-    assertThat(result.count).isEqualTo(959);
+    // Don't count the Genesis block
+    assertThat(result.count).isEqualTo(958);
   }
 }