diff --git a/.settings/.gitignore b/.settings/.gitignore
new file mode 100644
index 0000000..0450880
--- /dev/null
+++ b/.settings/.gitignore
@@ -0,0 +1,2 @@
+/org.eclipse.m2e.core.prefs
+/org.eclipse.wst.common.project.facet.core.xml
diff --git a/pom.xml b/pom.xml
index 8f8a82d..28bfabf 100644
--- a/pom.xml
+++ b/pom.xml
@@ -20,7 +20,7 @@
     <dependency>
       <groupId>org.antlr</groupId>
       <artifactId>antlr4-runtime</artifactId>
-      <version>4.2</version>
+      <version>4.5.1</version>
     </dependency>
     <dependency>
       <groupId>org.antlr</groupId>
@@ -94,6 +94,26 @@
       <artifactId>slf4j-log4j12</artifactId>
       <version>1.7.5</version>
     </dependency>
+    <dependency>
+      <groupId>eu.clarin.sru.fcs</groupId>
+      <artifactId>fcs-simple-endpoint</artifactId>
+      <version>1.3.0</version>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.lucene</groupId>
+      <artifactId>lucene-core</artifactId>
+      <version>5.2.1</version>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.lucene</groupId>
+      <artifactId>lucene-analyzers-common</artifactId>
+      <version>5.2.1</version>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.lucene</groupId>
+      <artifactId>lucene-queryparser</artifactId>
+      <version>5.2.1</version>
+    </dependency>
   </dependencies>
   <build>
     <sourceDirectory>${basedir}/src/main/java</sourceDirectory>
diff --git a/src/main/java/de/ids_mannheim/korap/query/serialize/CqlQueryProcessor.java b/src/main/java/de/ids_mannheim/korap/query/serialize/CqlQueryProcessor.java
index b06731c..e2070bf 100644
--- a/src/main/java/de/ids_mannheim/korap/query/serialize/CqlQueryProcessor.java
+++ b/src/main/java/de/ids_mannheim/korap/query/serialize/CqlQueryProcessor.java
@@ -22,16 +22,12 @@
     private static final String INDEX_WORDS = "words";
     private static final String TERM_RELATION_CQL_1_1 = "scr";
     private static final String TERM_RELATION_CQL_1_2 = "=";
-    private static final String SUPPORTED_RELATION_EXACT = "exact"; // not
-                                                                    // in
-                                                                    // the
-                                                                    // doc
+    private static final String SUPPORTED_RELATION_EXACT = "exact"; // not in the doc
     private static final String OPERATION_OR = "operation:or";
     private static final String OPERATION_SEQUENCE = "operation:sequence";
     private static final String OPERATION_POSITION = "operation:position";
     private static final String KORAP_CONTEXT = "http://ids-mannheim.de/ns/KorAP/json-ld/v0.1/context.jsonld";
 
-    private LinkedHashMap<String, Object> requestMap;
     private String version;
     private boolean isCaseSensitive; // default true
 
@@ -40,12 +36,10 @@
         this(query, VERSION_1_2, true);
     }
 
-
     public CqlQueryProcessor (String query, String version) {
         this(query, version, true);
     }
 
-
     public CqlQueryProcessor (String query, String version,
                               boolean isCaseSensitive) {
         this.version = version;
@@ -55,13 +49,11 @@
         process(query);
     }
 
-
     @Override
     public Map<String, Object> getRequestMap () {
         return this.requestMap;
     }
 
-
     @Override
     public void process (String query) {
         if ((query == null) || query.isEmpty())
diff --git a/src/main/java/de/ids_mannheim/korap/query/serialize/FCSQLQueryProcessor.java b/src/main/java/de/ids_mannheim/korap/query/serialize/FCSQLQueryProcessor.java
new file mode 100644
index 0000000..7e0c199
--- /dev/null
+++ b/src/main/java/de/ids_mannheim/korap/query/serialize/FCSQLQueryProcessor.java
@@ -0,0 +1,269 @@
+package de.ids_mannheim.korap.query.serialize;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import de.ids_mannheim.korap.query.serialize.util.StatusCodes;
+import eu.clarin.sru.server.SRUQueryBase;
+import eu.clarin.sru.server.SRUVersion;
+import eu.clarin.sru.server.fcs.Constants;
+import eu.clarin.sru.server.fcs.parser.Expression;
+import eu.clarin.sru.server.fcs.parser.Operator;
+import eu.clarin.sru.server.fcs.parser.QueryNode;
+import eu.clarin.sru.server.fcs.parser.QueryParser;
+import eu.clarin.sru.server.fcs.parser.QueryParserException;
+import eu.clarin.sru.server.fcs.parser.QuerySegment;
+import eu.clarin.sru.server.fcs.parser.RegexFlag;
+
+public class FCSQLQueryProcessor extends AbstractQueryProcessor {
+
+	public static final class FCSQuery extends SRUQueryBase<QueryNode> {
+
+		private FCSQuery(String rawQuery, QueryNode parsedQuery) {
+			super(rawQuery, parsedQuery);
+		}
+
+		@Override
+		public String getQueryType() {
+			return Constants.FCS_QUERY_TYPE_FCS;
+		}
+	}
+
+	public enum Foundry {
+		CNX, OPENNLP, TT, MATE, XIP;
+	}
+
+	private static final String KORAP_CONTEXT = "http://ids-mannheim.de/ns/KorAP/json-ld/v0.1/context.jsonld";
+	private String version;
+	private List<Foundry> supportedFoundries;
+	private final QueryParser parser = new QueryParser();
+
+	public FCSQLQueryProcessor(String query, String version) {
+		if (version == null) {
+			addError(StatusCodes.MISSING_VERSION,
+					"SRU Diagnostic 7: Version number is missing.");
+		} else if (!version.equals(SRUVersion.VERSION_2_0)) {
+			addError(StatusCodes.MISSING_VERSION,
+					"SRU Diagnostic 5: Only supports SRU version 2.0.");
+		}
+		this.version = version;
+
+		this.requestMap = new LinkedHashMap<>();
+		requestMap.put("@context", KORAP_CONTEXT);
+
+		this.supportedFoundries = new ArrayList<Foundry>(5);
+		supportedFoundries.add(Foundry.CNX);
+		supportedFoundries.add(Foundry.OPENNLP);
+		supportedFoundries.add(Foundry.TT);
+		supportedFoundries.add(Foundry.MATE);
+		supportedFoundries.add(Foundry.XIP);
+
+		process(query);
+	}
+
+	@Override
+	public Map<String, Object> getRequestMap() {
+		return this.requestMap;
+	}
+
+	@Override
+	public void process(String query) {
+		FCSQuery fcsQuery = parseQueryStringtoFCSQuery(query);
+		QueryNode fcsQueryNode = fcsQuery.getParsedQuery();
+		Map<String, Object> queryMap = parseFCSQuery(fcsQueryNode);
+		requestMap.put("query", queryMap);
+	}
+
+	private FCSQuery parseQueryStringtoFCSQuery(String query) {
+		if ((query == null) || query.isEmpty())
+			addError(StatusCodes.MALFORMED_QUERY,
+					"SRU diagnostic 1: No query has been passed.");
+		FCSQuery fcsQuery = null;
+		try {
+			QueryNode parsedQuery = parser.parse(query);
+			fcsQuery = new FCSQuery(query, parsedQuery);
+		} catch (QueryParserException e) {
+			addError(StatusCodes.UNKNOWN_QUERY_ERROR, "FCS Diagnostic 10: +"
+					+ e.getMessage());
+		}
+		catch (Exception e) {
+			addError(StatusCodes.UNKNOWN_QUERY_ERROR, "FCS Diagnostic 10: +"
+					+ "Unexpected error while parsing query.");
+		}
+		return fcsQuery;
+	}
+
+	private Map<String, Object> parseFCSQuery(QueryNode queryNode) {
+		Map<String, Object> queryMap = parseQueryNode(queryNode);
+		if (queryMap == null) {
+			addError(StatusCodes.UNKNOWN_QUERY_ERROR, "SRU diagnostic 47:"
+					+ " Failed parsing query for unknown reasons.");
+		}
+		return queryMap;
+
+	}
+
+	private Map<String, Object> parseQueryNode(QueryNode queryNode) {
+		Map<String, Object> queryMap = null;
+
+		if (queryNode instanceof QuerySegment) {
+			queryMap = parseQuerySegment((QuerySegment) queryNode);
+//		} else if (queryNode instanceof QueryGroup) {
+//
+//		} else if (queryNode instanceof QuerySequence) {
+//
+//		} else if (queryNode instanceof QueryDisjunction) {
+//
+//		} else if (queryNode instanceof QueryWithWithin) {
+
+		}else {
+			addError(StatusCodes.QUERY_TOO_COMPLEX, "FCS diagnostic 11:"
+					+ queryNode.getNodeType().name()
+					+ " is currently unsupported.");
+		}
+
+		return queryMap;
+	}
+
+	private Map<String, Object> parseQuerySegment(QuerySegment segment) {
+		Map<String, Object> queryMap = null;
+
+		if ((segment.getMinOccurs() == 1) && (segment.getMaxOccurs() == 1)) {
+			queryMap = parseExpression(segment.getExpression());
+		} else {
+			addError(StatusCodes.QUERY_TOO_COMPLEX, "FCS diagnostic 11:"
+					+ "Query is too complex.");
+		}
+		return queryMap;
+	}
+
+	private Map<String, Object> parseExpression(QueryNode queryNode) {
+		Map<String, Object> queryMap = null;
+
+		if (queryNode instanceof Expression) {
+			Expression expression = (Expression) queryNode;
+			queryMap = parseLayer(expression);
+		}
+		// else if (queryNode instanceof ExpressionAnd) {
+		//
+		// }
+		// else if (queryNode instanceof ExpressionGroup) {
+		//
+		// }
+		// else if (queryNode instanceof ExpressionNot) {
+		//
+		// }
+		// else if (queryNode instanceof ExpressionOr) {
+		//
+		// }
+		// else if (queryNode instanceof ExpressionWildcard) {
+		//
+		// }
+		else {
+			addError(StatusCodes.QUERY_TOO_COMPLEX, "FCS diagnostic 11:"
+					+ "Query is too complex.");
+		}
+		return queryMap;
+	}
+
+	private Map<String, Object> parseLayer(Expression expression) {
+		String layer = parseLayerIdentifier(expression.getLayerIdentifier());
+		String foundry = parseQualifier(expression.getLayerQualifier(), layer);
+		String operator = parseOperator(expression.getOperator());
+		boolean isCaseSensitive = parseRegexFlags(expression.getRegexFlags());		
+		String term = expression.getRegexValue();
+		
+		return writeTerm(term, foundry, layer, operator, isCaseSensitive);
+	}
+	private String parseLayerIdentifier(String identifier) {
+		String layer = null;
+		if (identifier == null) {
+			// throw exception
+		} else if (identifier.equals("text")) {
+			layer = "orth";
+		} else if (identifier.equals("pos")) {
+			layer = "p";
+		} else if (identifier.equals("lemma")) {
+			layer = "l";
+		} else {
+			addError(StatusCodes.UNKNOWN_QUERY_ELEMENT, "SRU diagnostic 48:"
+					+ identifier + " is unsupported.");
+		}
+
+		return layer;
+	}
+	
+	private String parseQualifier(String qualifier, String layer) {
+		// Set default foundry
+		if (qualifier == null) {
+			if (layer.equals("orth")) {
+				qualifier = Foundry.OPENNLP.name().toLowerCase();
+			} else {
+				qualifier = Foundry.TT.name().toLowerCase();
+			}
+		} else if (qualifier.equals(Foundry.OPENNLP.name().toLowerCase())
+				&& layer.equals("lemma")) {
+			addError(StatusCodes.UNKNOWN_QUERY_ELEMENT, "SRU diagnostic 48:"
+					+ "Layer lemma with qualifier opennlp is unsupported.");
+		} else if (!supportedFoundries.contains(qualifier)) {
+			addError(StatusCodes.UNKNOWN_QUERY_ELEMENT, "SRU diagnostic 48:"
+					+ "Layer " + layer + " with qualifier" + qualifier
+					+ " is unsupported.");
+		}
+		return qualifier;
+	}
+	
+	private String parseOperator(Operator operator) {
+		String matchOperator = null;
+		if (operator == null || operator == Operator.EQUALS) {
+			matchOperator = "match:eq";
+		} else if (operator == Operator.NOT_EQUALS) {
+			matchOperator = "match:ne";
+		} else {
+			addError(StatusCodes.UNKNOWN_QUERY_ELEMENT, "SRU diagnostic 37:"
+					+ operator.name() + " is unsupported.");
+		}
+		return matchOperator;
+	}
+	
+	private boolean parseRegexFlags(Set<RegexFlag> set) {
+		// default case sensitive
+		boolean flag = true;
+		if (set != null) {
+			for (RegexFlag f : set) {
+				if (f == RegexFlag.CASE_SENSITVE) {
+					continue;
+				} else if (f == RegexFlag.CASE_INSENSITVE) {
+					flag = false;
+				} else {
+					addError(StatusCodes.UNKNOWN_QUERY_ELEMENT,
+							"SRU diagnostic 48:" + f.name()
+									+ " is unsupported.");
+				}
+			}
+		}
+		return flag;
+	}
+
+	private Map<String, Object> writeTerm(String term, String foundry,
+			String layer, String operator, boolean isCaseSensitive) {
+		Map<String, Object> map = new LinkedHashMap<String, Object>();
+		map.put("@type", "koral:term");
+		if (!isCaseSensitive) {
+			map.put("caseInsensitive", "true");
+		}
+		map.put("key", term);
+		map.put("foundry", foundry);
+		map.put("layer", layer);
+		map.put("match", operator);
+
+		Map<String, Object> tokenMap = new LinkedHashMap<String, Object>();
+		tokenMap.put("@type", "koral:token");
+		tokenMap.put("wrap", map);
+		return tokenMap;
+	}
+
+}
diff --git a/src/main/java/de/ids_mannheim/korap/query/serialize/QuerySerializer.java b/src/main/java/de/ids_mannheim/korap/query/serialize/QuerySerializer.java
index 643eb08..b2cd727 100644
--- a/src/main/java/de/ids_mannheim/korap/query/serialize/QuerySerializer.java
+++ b/src/main/java/de/ids_mannheim/korap/query/serialize/QuerySerializer.java
@@ -16,7 +16,8 @@
  * KoralQuery
  *
  * @author Joachim Bingel (bingel@ids-mannheim.de),
- *         Michael Hanl (hanl@ids-mannheim.de)
+ *         Michael Hanl (hanl@ids-mannheim.de),
+ *         Eliza Margaretha (margaretha@ids-mannheim.de)
  * @version 0.3.0
  * @since 0.1.0
  */
@@ -111,6 +112,8 @@
             ast = new PoliqarpPlusQueryProcessor(query);
         }else if (queryLanguage.equalsIgnoreCase("cql")) {
             ast = new CqlQueryProcessor(query);
+		} else if (queryLanguage.equalsIgnoreCase("fcsql")) {
+			ast = new FCSQLQueryProcessor(query, "2.0");
         }else if (queryLanguage.equalsIgnoreCase("annis")) {
             ast = new AnnisQueryProcessor(query);
         }else {
@@ -134,14 +137,22 @@
         }else if (ql.equalsIgnoreCase("poliqarpplus")) {
             ast = new PoliqarpPlusQueryProcessor(query);
         }else if (ql.equalsIgnoreCase("cql")) {
-            if (version == null)
+			if (version == null) {
                 ast = new CqlQueryProcessor(query);
-            else
+			} else {
                 ast = new CqlQueryProcessor(query, version);
-        }else if (ql.equalsIgnoreCase("annis")) {
+			}
+		} else if (ql.equalsIgnoreCase("fcsql")) {
+			if (version == null) {
+				ast.addError(StatusCodes.MISSING_VERSION,
+						"SRU Version is missing!");
+			} else {
+				ast = new FCSQLQueryProcessor(query, version);
+			}
+		} else if (ql.equalsIgnoreCase("annis")) {
             ast = new AnnisQueryProcessor(query);
         }else {
-            ast.addError(StatusCodes.UNKNOWN_QL,
+			ast.addError(StatusCodes.UNKNOWN_QUERY_LANGUAGE,
                     ql + " is not a supported query language!");
         }
         return this;
diff --git a/src/main/java/de/ids_mannheim/korap/query/serialize/util/StatusCodes.java b/src/main/java/de/ids_mannheim/korap/query/serialize/util/StatusCodes.java
index 10614ea..1f896b3 100644
--- a/src/main/java/de/ids_mannheim/korap/query/serialize/util/StatusCodes.java
+++ b/src/main/java/de/ids_mannheim/korap/query/serialize/util/StatusCodes.java
@@ -7,7 +7,9 @@
     public final static int INVALID_CLASS_REFERENCE = 304;
     public final static int INCOMPATIBLE_OPERATOR_AND_OPERAND = 305;
     public final static int UNKNOWN_QUERY_ELEMENT = 306;
-    public final static int UNKNOWN_QL = 307;
+	public final static int UNKNOWN_QUERY_LANGUAGE = 307;
     public final static int UNBOUND_ANNIS_RELATION = 308;
-    public final static int UNKNOWN_QUERY_ERROR = 399;
-}
+	public final static int MISSING_VERSION = 309;
+	public final static int QUERY_TOO_COMPLEX = 310;
+	public final static int UNKNOWN_QUERY_ERROR = 399;
+}
\ No newline at end of file
diff --git a/src/test/java/de/ids_mannheim/korap/query/serialize/FcsqlQueryProcessorTest.java b/src/test/java/de/ids_mannheim/korap/query/serialize/FcsqlQueryProcessorTest.java
new file mode 100644
index 0000000..729381e
--- /dev/null
+++ b/src/test/java/de/ids_mannheim/korap/query/serialize/FcsqlQueryProcessorTest.java
@@ -0,0 +1,90 @@
+package de.ids_mannheim.korap.query.serialize;
+
+import static org.junit.Assert.assertEquals;
+
+
+import org.junit.Test;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+public class FcsqlQueryProcessorTest {
+	ObjectMapper mapper = new ObjectMapper();
+
+	private void runAndValidate(String query, String jsonLD)
+			throws JsonProcessingException {
+		FCSQLQueryProcessor tree = new FCSQLQueryProcessor(query, "2.0");
+		String serializedQuery = mapper.writeValueAsString(tree.getRequestMap()
+				.get("query"));
+		assertEquals(jsonLD.replace(" ", ""), serializedQuery.replace("\"", ""));
+	}
+
+	@Test
+	public void testTermQuery() throws JsonProcessingException {
+		String query = "\"Sonne\"";
+		String jsonLd = "{@type:koral:token, wrap:{@type:koral:term, key:Sonne, "
+				+ "foundry:opennlp, layer:orth, match:match:eq}}";
+		runAndValidate(query, jsonLd);
+	}
+
+	@Test
+	public void testTermQueryWithRegexFlag() throws JsonProcessingException {
+		String query = "\"Fliegen\" /c";
+		String jsonLd = "{@type:koral:token, wrap:{@type:koral:term, caseInsensitive:true, "
+				+ "key:Fliegen, foundry:opennlp, layer:orth, match:match:eq}}";
+		runAndValidate(query, jsonLd);
+	}
+
+	@Test
+	public void testTermQueryWithSpecificLayer() throws JsonProcessingException {
+		String query = "[text = \"Sonne\"]";
+		String jsonLd = "{@type:koral:token, wrap:{@type:koral:term, key:Sonne, "
+				+ "foundry:opennlp, layer:orth, match:match:eq}}";
+		runAndValidate(query, jsonLd);
+
+		query = "[lemma = \"sein\"]";
+		jsonLd = "{@type:koral:token, wrap:{@type:koral:term, key:sein, "
+				+ "foundry:tt, layer:l, match:match:eq}}";
+		runAndValidate(query, jsonLd);
+
+		query = "[pos = \"NN\"]";
+		jsonLd = "{@type:koral:token, wrap:{@type:koral:term, key:NN, "
+				+ "foundry:tt, layer:p, match:match:eq}}";
+		runAndValidate(query, jsonLd);
+	}
+
+	@Test
+	public void testTermQueryWithQualifier() throws JsonProcessingException {
+		String query = "[mate:lemma = \"sein\"]";
+		String jsonLd = "{@type:koral:token, wrap:{@type:koral:term, key:sein, "
+				+ "foundry:mate, layer:l, match:match:eq}}";
+		runAndValidate(query, jsonLd);
+
+		query = "[cnx:pos = \"N\"]";
+		jsonLd = "{@type:koral:token, wrap:{@type:koral:term, key:N, "
+				+ "foundry:cnx, layer:p, match:match:eq}}";
+		runAndValidate(query, jsonLd);
+	}
+
+	@Test
+	public void testMatchOperation() throws JsonProcessingException {
+		String query = "[cnx:pos != \"N\"]";
+		String jsonLd = "{@type:koral:token, wrap:{@type:koral:term, key:N, "
+				+ "foundry:cnx, layer:p, match:match:ne}}";
+		runAndValidate(query, jsonLd);
+	}
+
+	// @Test
+	// public void testSequenceQuery() throws JsonProcessingException {
+	// String query = "\"blaue\" [pos = \"NN\"]";
+	// String jsonLd =
+	// "{@type:koral:group, operation:operation:sequence, operands:["
+	// +
+	// "{@type:koral:token, wrap:{@type:koral:term, key:blaue, foundry:opennlp, layer:orth, match:match:eq}},"
+	// +
+	// "{@type:koral:token, wrap:{@type:koral:term, key:NN, foundry:tt, layer:p, match:match:eq}}"
+	// + "]}";
+	// runAndValidate(query, jsonLd);
+	// }
+
+}