diff --git a/linker/linker_config.cpp b/linker/linker_config.cpp
index f7d2c53..b203569 100644
--- a/linker/linker_config.cpp
+++ b/linker/linker_config.cpp
@@ -49,7 +49,8 @@
 class ConfigParser {
  public:
   enum {
-    kProperty,
+    kPropertyAssign,
+    kPropertyAppend,
     kSection,
     kEndOfFile,
     kError,
@@ -60,7 +61,8 @@
 
   /*
    * Possible return values
-   * kProperty: name is set to property name and value is set to property value
+   * kPropertyAssign: name is set to property name and value is set to property value
+   * kPropertyAppend: same as kPropertyAssign, but the value should be appended
    * kSection: name is set to section name.
    * kEndOfFile: reached end of file.
    * kError: error_msg is set.
@@ -80,17 +82,24 @@
         return kSection;
       }
 
-      found = line.find('=');
-      if (found == std::string::npos) {
-        *error_msg = std::string("invalid format: ") +
-                    line +
-                    ", expected \"name = property\" or \"[section]\"";
-        return kError;
+      size_t found_assign = line.find('=');
+      size_t found_append = line.find("+=");
+      if (found_assign != std::string::npos && found_append == std::string::npos) {
+        *name = android::base::Trim(line.substr(0, found_assign));
+        *value = android::base::Trim(line.substr(found_assign + 1));
+        return kPropertyAssign;
       }
 
-      *name = android::base::Trim(line.substr(0, found));
-      *value = android::base::Trim(line.substr(found + 1));
-      return kProperty;
+      if (found_append != std::string::npos) {
+        *name = android::base::Trim(line.substr(0, found_append));
+        *value = android::base::Trim(line.substr(found_append + 2));
+        return kPropertyAppend;
+      }
+
+      *error_msg = std::string("invalid format: ") +
+                   line +
+                   ", expected \"name = property\", \"name += property\", or \"[section]\"";
+      return kError;
     }
 
     // to avoid infinite cycles when programmer makes a mistake
@@ -141,6 +150,14 @@
     return value_;
   }
 
+  void append_value(std::string&& value) {
+    value_ = value_ + value;
+    // lineno isn't updated as we might have cases like this:
+    // property.x = blah
+    // property.y = blah
+    // property.x += blah
+  }
+
   size_t lineno() const {
     return lineno_;
   }
@@ -194,7 +211,7 @@
       return false;
     }
 
-    if (result == ConfigParser::kProperty) {
+    if (result == ConfigParser::kPropertyAssign) {
       if (!android::base::StartsWith(name, "dir.")) {
         DL_WARN("error parsing %s:%zd: unexpected property name \"%s\", "
                 "expected format dir.<section_name> (ignoring this line)",
@@ -255,7 +272,7 @@
       break;
     }
 
-    if (result == ConfigParser::kProperty) {
+    if (result == ConfigParser::kPropertyAssign) {
       if (properties->find(name) != properties->end()) {
         DL_WARN("%s:%zd: warning: property \"%s\" redefinition",
                 ld_config_file_path,
@@ -264,6 +281,29 @@
       }
 
       (*properties)[name] = PropertyValue(std::move(value), cp.lineno());
+    } else if (result == ConfigParser::kPropertyAppend) {
+      if (properties->find(name) == properties->end()) {
+        DL_WARN("%s:%zd: warning: appending to property \"%s\" which isn't defined",
+                ld_config_file_path,
+                cp.lineno(),
+                name.c_str());
+        (*properties)[name] = PropertyValue(std::move(value), cp.lineno());
+      } else {
+        if (android::base::EndsWith(name, ".links") ||
+            android::base::EndsWith(name, ".namespaces")) {
+          value = "," + value;
+          (*properties)[name].append_value(std::move(value));
+        } else if (android::base::EndsWith(name, ".paths") ||
+                   android::base::EndsWith(name, ".shared_libs")) {
+          value = ":" + value;
+          (*properties)[name].append_value(std::move(value));
+        } else {
+          DL_WARN("%s:%zd: warning: += isn't allowed to property \"%s\". Ignoring.",
+                  ld_config_file_path,
+                  cp.lineno(),
+                  name.c_str());
+        }
+      }
     }
 
     if (result == ConfigParser::kError) {
diff --git a/linker/tests/linker_config_test.cpp b/linker/tests/linker_config_test.cpp
index c6fade9..4c0dcdd 100644
--- a/linker/tests/linker_config_test.cpp
+++ b/linker/tests/linker_config_test.cpp
@@ -56,19 +56,31 @@
   "\n"
   "enable.target.sdk.version = true\n"
   "additional.namespaces=system\n"
+  "additional.namespaces+=vndk\n"
   "namespace.default.isolated = true\n"
   "namespace.default.search.paths = /vendor/${LIB}\n"
   "namespace.default.permitted.paths = /vendor/${LIB}\n"
-  "namespace.default.asan.search.paths = /data:/vendor/${LIB}\n"
+  "namespace.default.asan.search.paths = /data\n"
+  "namespace.default.asan.search.paths += /vendor/${LIB}\n"
   "namespace.default.asan.permitted.paths = /data:/vendor\n"
   "namespace.default.links = system\n"
-  "namespace.default.link.system.shared_libs = libc.so:libm.so:libdl.so:libstdc++.so\n"
+  "namespace.default.links += vndk\n"
+  // irregular whitespaces are added intentionally for testing purpose
+  "namespace.default.link.system.shared_libs=  libc.so\n"
+  "namespace.default.link.system.shared_libs +=   libm.so:libdl.so\n"
+  "namespace.default.link.system.shared_libs   +=libstdc++.so\n"
+  "namespace.default.link.vndk.shared_libs = libcutils.so:libbase.so\n"
   "namespace.system.isolated = true\n"
   "namespace.system.visible = true\n"
   "namespace.system.search.paths = /system/${LIB}\n"
   "namespace.system.permitted.paths = /system/${LIB}\n"
   "namespace.system.asan.search.paths = /data:/system/${LIB}\n"
   "namespace.system.asan.permitted.paths = /data:/system\n"
+  "namespace.vndk.isolated = tr\n"
+  "namespace.vndk.isolated += ue\n" // should be ignored and return as 'false'.
+  "namespace.vndk.search.paths = /system/${LIB}/vndk\n"
+  "namespace.vndk.asan.search.paths = /data\n"
+  "namespace.vndk.asan.search.paths += /system/${LIB}/vndk\n"
   "\n";
 
 static bool write_version(const std::string& path, uint32_t version) {
@@ -99,6 +111,10 @@
       resolve_paths(is_asan ? std::vector<std::string>({ "/data", "/system" }) :
                               std::vector<std::string>({ "/system/lib" ARCH_SUFFIX }));
 
+  const std::vector<std::string> kExpectedVndkSearchPath =
+      resolve_paths(is_asan ? std::vector<std::string>({ "/data", "/system/lib" ARCH_SUFFIX "/vndk"}) :
+                              std::vector<std::string>({ "/system/lib" ARCH_SUFFIX "/vndk"}));
+
   TemporaryFile tmp_file;
   close(tmp_file.fd);
   tmp_file.fd = -1;
@@ -137,22 +153,27 @@
   ASSERT_EQ(kExpectedDefaultPermittedPath, default_ns_config->permitted_paths());
 
   const auto& default_ns_links = default_ns_config->links();
-  ASSERT_EQ(1U, default_ns_links.size());
+  ASSERT_EQ(2U, default_ns_links.size());
   ASSERT_EQ("system", default_ns_links[0].ns_name());
   ASSERT_EQ("libc.so:libm.so:libdl.so:libstdc++.so", default_ns_links[0].shared_libs());
+  ASSERT_EQ("vndk", default_ns_links[1].ns_name());
+  ASSERT_EQ("libcutils.so:libbase.so", default_ns_links[1].shared_libs());
 
   auto& ns_configs = config->namespace_configs();
-  ASSERT_EQ(2U, ns_configs.size());
+  ASSERT_EQ(3U, ns_configs.size());
 
   // find second namespace
   const NamespaceConfig* ns_system = nullptr;
+  const NamespaceConfig* ns_vndk = nullptr;
   for (auto& ns : ns_configs) {
     std::string ns_name = ns->name();
-    ASSERT_TRUE(ns_name == "system" || ns_name == "default")
+    ASSERT_TRUE(ns_name == "system" || ns_name == "default" || ns_name == "vndk")
         << "unexpected ns name: " << ns->name();
 
     if (ns_name == "system") {
       ns_system = ns.get();
+    } else if (ns_name == "vndk") {
+      ns_vndk = ns.get();
     }
   }
 
@@ -162,6 +183,12 @@
   ASSERT_TRUE(ns_system->visible());
   ASSERT_EQ(kExpectedSystemSearchPath, ns_system->search_paths());
   ASSERT_EQ(kExpectedSystemPermittedPath, ns_system->permitted_paths());
+
+  ASSERT_TRUE(ns_vndk != nullptr) << "vndk namespace was not found";
+
+  ASSERT_FALSE(ns_vndk->isolated()); // malformed bool property
+  ASSERT_FALSE(ns_vndk->visible()); // undefined bool property 
+  ASSERT_EQ(kExpectedVndkSearchPath, ns_vndk->search_paths());
 }
 
 TEST(linker_config, smoke) {