Index: include-fixer/SymbolIndexManager.cpp
===================================================================
--- include-fixer/SymbolIndexManager.cpp
+++ include-fixer/SymbolIndexManager.cpp
@@ -17,6 +17,37 @@
 namespace clang {
 namespace include_fixer {
 
+using clang::find_all_symbols::SymbolInfo;
+
+/// Sorts and uniques SymbolInfos based on the popularity info in SymbolInfo.
+static void rankByPopularity(std::vector<SymbolInfo> &Symbols) {
+  // First collect occurrences per header file.
+  std::map<llvm::StringRef, unsigned> HeaderPopularity;
+  for (const SymbolInfo &Symbol : Symbols) {
+    unsigned &Popularity = HeaderPopularity[Symbol.getFilePath()];
+    Popularity = std::max(Popularity, Symbol.getNumOccurrences());
+  }
+
+  // Sort by the gathered popularities. Use file name as a tie breaker so we can
+  // deduplicate.
+  std::sort(Symbols.begin(), Symbols.end(),
+            [&](const SymbolInfo &A, const SymbolInfo &B) {
+              auto APop = HeaderPopularity[A.getFilePath()];
+              auto BPop = HeaderPopularity[B.getFilePath()];
+              if (APop != BPop)
+                return APop > BPop;
+              return A.getFilePath() < B.getFilePath();
+            });
+
+  // Deduplicate based on the file name. They will have the same popularity and
+  // we don't want to suggest the same header twice.
+  Symbols.erase(std::unique(Symbols.begin(), Symbols.end(),
+                            [](const SymbolInfo &A, const SymbolInfo &B) {
+                              return A.getFilePath() == B.getFilePath();
+                            }),
+                Symbols.end());
+}
+
 std::vector<std::string>
 SymbolIndexManager::search(llvm::StringRef Identifier) const {
   // The identifier may be fully qualified, so split it and get all the context
@@ -45,6 +76,8 @@
     DEBUG(llvm::dbgs() << "Searching " << Names.back() << "... got "
                        << Symbols.size() << " results...\n");
 
+    rankByPopularity(Symbols);
+
     for (const auto &Symbol : Symbols) {
       // Match the identifier name without qualifier.
       if (Symbol.getName() == Names.back()) {
Index: include-fixer/tool/ClangIncludeFixer.cpp
===================================================================
--- include-fixer/tool/ClangIncludeFixer.cpp
+++ include-fixer/tool/ClangIncludeFixer.cpp
@@ -98,11 +98,11 @@
       std::vector<std::string> Headers;
       SmallVector<StringRef, 4> CommaSplits;
       Split.second.split(CommaSplits, ",");
-      for (StringRef Header : CommaSplits)
+      for (const StringRef &Header : CommaSplits)
         Symbols.push_back(find_all_symbols::SymbolInfo(
             Split.first.trim(),
             find_all_symbols::SymbolInfo::SymbolKind::Unknown, Header.trim(), 1,
-            {}));
+            {}, /*NumOccurrences=*/CommaSplits.end() - &Header));
     }
     SymbolIndexMgr->addSymbolIndex(
         llvm::make_unique<include_fixer::InMemorySymbolIndex>(Symbols));
Index: test/include-fixer/Inputs/fake_yaml_db.yaml
===================================================================
--- test/include-fixer/Inputs/fake_yaml_db.yaml
+++ test/include-fixer/Inputs/fake_yaml_db.yaml
@@ -22,3 +22,24 @@
 Type:            Class
 NumOccurrences:  1
 ...
+Name:           bar
+Contexts:
+  - ContextType:     Namespace
+    ContextName:     a
+  - ContextType:     Namespace
+    ContextName:     b
+FilePath:        ../include/bar.h
+LineNumber:      2
+Type:            Class
+NumOccurrences:  3
+...
+Name:           bar
+Contexts:
+  - ContextType:     Namespace
+    ContextName:     a
+  - ContextType:     Namespace
+    ContextName:     b
+FilePath:        ../include/zbar.h
+LineNumber:      1
+Type:            Class
+NumOccurrences:  3
Index: test/include-fixer/ranking.cpp
===================================================================
--- /dev/null
+++ test/include-fixer/ranking.cpp
@@ -0,0 +1,6 @@
+// RUN: clang-include-fixer -db=yaml -input=%S/Inputs/fake_yaml_db.yaml -output-headers %s -- | FileCheck %s -implicit-check-not=.h
+
+// CHECK: "../include/bar.h"
+// CHECK-NEXT: "../include/zbar.h"
+
+bar b;