diff --git a/include/E57Format.h b/include/E57Format.h
index 8123bf4..21edff3 100644
--- a/include/E57Format.h
+++ b/include/E57Format.h
@@ -485,7 +485,7 @@ public:
 
       // Iterators
       CompressedVectorWriter writer( std::vector<SourceDestBuffer> &sbufs );
-      CompressedVectorReader reader( const std::vector<SourceDestBuffer> &dbufs );
+      CompressedVectorReader reader( const std::vector<SourceDestBuffer> &dbufs, bool allowParallel = false );
 
       // Up/Down cast conversion
       operator Node() const;
diff --git a/src/CompressedVectorNode.cpp b/src/CompressedVectorNode.cpp
index 9de177d..fff1014 100644
--- a/src/CompressedVectorNode.cpp
+++ b/src/CompressedVectorNode.cpp
@@ -474,7 +474,7 @@ prototype. It is not an error to create a CompressedVectorReader for an empty Co
 @see CompressedVectorReader, SourceDestBuffer, CompressedVectorNode::CompressedVectorNode,
 CompressedVectorNode::prototype
 */
-CompressedVectorReader CompressedVectorNode::reader( const std::vector<SourceDestBuffer> &dbufs )
+CompressedVectorReader CompressedVectorNode::reader( const std::vector<SourceDestBuffer> &dbufs, bool allowParallel )
 {
-   return CompressedVectorReader( impl_->reader( dbufs ) );
+   return CompressedVectorReader( impl_->reader( dbufs, allowParallel ) );
 }
diff --git a/src/CompressedVectorNodeImpl.cpp b/src/CompressedVectorNodeImpl.cpp
index 3f344ba..9cb271c 100644
--- a/src/CompressedVectorNodeImpl.cpp
+++ b/src/CompressedVectorNodeImpl.cpp
@@ -318,7 +318,8 @@ namespace e57
    }
 
    std::shared_ptr<CompressedVectorReaderImpl> CompressedVectorNodeImpl::reader(
-      std::vector<SourceDestBuffer> dbufs )
+      std::vector<SourceDestBuffer> dbufs,
+      bool allowParallel )
    {
       checkImageFileOpen( __FILE__, __LINE__, static_cast<const char *>( __FUNCTION__ ) );
 
@@ -332,7 +333,7 @@ namespace e57
                                   " writerCount=" + toString( destImageFile->writerCount() ) +
                                   " readerCount=" + toString( destImageFile->readerCount() ) );
       }
-      if ( destImageFile->readerCount() > 0 )
+      if ( !allowParallel && destImageFile->readerCount() > 0 )
       {
          throw E57_EXCEPTION2( ErrorTooManyReaders,
                                "fileName=" + destImageFile->fileName() +
diff --git a/src/CompressedVectorNodeImpl.h b/src/CompressedVectorNodeImpl.h
index 82887bf..8203b2b 100644
--- a/src/CompressedVectorNodeImpl.h
+++ b/src/CompressedVectorNodeImpl.h
@@ -59,7 +59,7 @@ namespace e57
 
       /// Iterator constructors
       std::shared_ptr<CompressedVectorWriterImpl> writer( std::vector<SourceDestBuffer> sbufs );
-      std::shared_ptr<CompressedVectorReaderImpl> reader( std::vector<SourceDestBuffer> dbufs );
+      std::shared_ptr<CompressedVectorReaderImpl> reader( std::vector<SourceDestBuffer> dbufs, bool allowParallel );
 
       int64_t getRecordCount() const
       {