diff --git a/libtorrent/include/libtorrent/stat.hpp b/libtorrent/include/libtorrent/stat.hpp
index 8ef8da1b4..2424d5d6c 100755
--- a/libtorrent/include/libtorrent/stat.hpp
+++ b/libtorrent/include/libtorrent/stat.hpp
@@ -131,6 +131,8 @@ namespace libtorrent
 		// transfers from earlier connections.
 		void add_stat(size_type downloaded, size_type uploaded)
 		{
+			assert(downloaded >= 0);
+			assert(uploaded >= 0);
 			m_total_download_payload += downloaded;
 			m_total_upload_payload += uploaded;
 		}
diff --git a/libtorrent/include/libtorrent/torrent_handle.hpp b/libtorrent/include/libtorrent/torrent_handle.hpp
index 6fa8d1082..4bc33f85d 100755
--- a/libtorrent/include/libtorrent/torrent_handle.hpp
+++ b/libtorrent/include/libtorrent/torrent_handle.hpp
@@ -210,7 +210,15 @@ namespace libtorrent
 		{ none, requested, writing, finished };
 
 		tcp::endpoint peer;
+		// number of bytes downloaded in this block
+		unsigned bytes_progress:16;
+		// the total number of bytes in this block
+		unsigned block_size:16;
+		// the state this block is in (see block_state_t)
 		unsigned state:2;
+		// the number of peers that has requested this block
+		// typically 0 or 1. If > 1, this block is in
+		// end game mode
 		unsigned num_peers:14;
 	};
 
diff --git a/libtorrent/src/policy.cpp b/libtorrent/src/policy.cpp
index 5bdb32ca2..7a4fc50c5 100755
--- a/libtorrent/src/policy.cpp
+++ b/libtorrent/src/policy.cpp
@@ -267,6 +267,7 @@ namespace libtorrent
 				continue;
 			}
 
+			assert(p.num_peers(*i) == 0);
 			// ok, we found a piece that's not being downloaded
 			// by somebody else. request it from this peer
 			// and return
@@ -279,7 +280,7 @@ namespace libtorrent
 		// blocks as well, we cannot download anything
 		// more from this peer.
 
-		if (busy_pieces.empty())
+		if (busy_pieces.empty() || num_requests == 0)
 		{
 			c.send_block_requests();
 			return;
diff --git a/libtorrent/src/torrent.cpp b/libtorrent/src/torrent.cpp
index 6ed6dd65a..b4a5efcd1 100755
--- a/libtorrent/src/torrent.cpp
+++ b/libtorrent/src/torrent.cpp
@@ -2330,14 +2330,30 @@ namespace libtorrent
 //		size_type download = m_stat.total_payload_download();
 //		size_type done = boost::get<0>(bytes_done());
 //		assert(download >= done - m_initial_done);
+		std::map<piece_block, int> num_requests;
 		for (const_peer_iterator i = begin(); i != end(); ++i)
 		{
 			peer_connection const& p = *i->second;
+			for (std::deque<piece_block>::const_iterator i = p.request_queue().begin()
+				, end(p.request_queue().end()); i != end; ++i)
+				++num_requests[*i];
+			for (std::deque<piece_block>::const_iterator i = p.download_queue().begin()
+				, end(p.download_queue().end()); i != end; ++i)
+				++num_requests[*i];
 			torrent* associated_torrent = p.associated_torrent().lock().get();
 			if (associated_torrent != this)
 				assert(false);
 		}
 
+		if (has_picker())
+		{
+			for (std::map<piece_block, int>::iterator i = num_requests.begin()
+				, end(num_requests.end()); i != end; ++i)
+			{
+				assert(m_picker->num_peers(i->first) == i->second);
+			}
+		}
+
 		if (valid_metadata())
 		{
 			assert(m_abort || int(m_have_pieces.size()) == m_torrent_file.num_pieces());
diff --git a/libtorrent/src/torrent_handle.cpp b/libtorrent/src/torrent_handle.cpp
index 00877aa16..10e1172fa 100755
--- a/libtorrent/src/torrent_handle.cpp
+++ b/libtorrent/src/torrent_handle.cpp
@@ -765,27 +765,61 @@ namespace libtorrent
 		const std::vector<piece_picker::downloading_piece>& q
 			= p.get_download_queue();
 
+		int block_size = t->block_size();
+
 		for (std::vector<piece_picker::downloading_piece>::const_iterator i
 			= q.begin(); i != q.end(); ++i)
 		{
 			partial_piece_info pi;
 			pi.piece_state = (partial_piece_info::state_t)i->state;
 			pi.blocks_in_piece = p.blocks_in_piece(i->index);
+			int piece_size = t->torrent_file().piece_size(i->index);
 			for (int j = 0; j < pi.blocks_in_piece; ++j)
 			{
+				block_info& bi = pi.blocks[j];
+				bi.state = i->info[j].state;
+				bi.block_size = j < pi.blocks_in_piece - 1 ? block_size
+					: piece_size - (j * block_size);
+				bool complete = bi.state == block_info::writing
+					|| bi.state == block_info::finished;
 				if (i->info[j].peer == 0)
-					pi.blocks[j].peer = tcp::endpoint();
+				{
+					bi.peer = tcp::endpoint();
+					bi.bytes_progress = complete ? bi.block_size : 0;
+				}
 				else
 				{
 					policy::peer* p = static_cast<policy::peer*>(i->info[j].peer);
 					if (p->connection)
-						pi.blocks[j].peer = p->connection->remote();
+					{
+						bi.peer = p->connection->remote();
+						if (bi.state == block_info::requested)
+						{
+							boost::optional<piece_block_progress> pbp
+								= p->connection->downloading_piece_progress();
+							if (pbp && pbp->piece_index == i->index && pbp->block_index == j)
+							{
+								bi.bytes_progress = pbp->bytes_downloaded;
+								assert(bi.bytes_progress <= bi.block_size);
+							}
+							else
+							{
+								bi.bytes_progress = 0;
+							}
+						}
+						else
+						{
+							bi.bytes_progress = complete ? bi.block_size : 0;
+						}
+					}
 					else
-						pi.blocks[j].peer = p->ip;
+					{
+						bi.peer = p->ip;
+						bi.bytes_progress = complete ? bi.block_size : 0;
+					}
 				}
 
 				pi.blocks[j].num_peers = i->info[j].num_peers;
-				pi.blocks[j].state = i->info[j].state;
 			}
 			pi.piece_index = i->index;
 			queue.push_back(pi);