diff --git a/walkthroughs/week-5-tdd/project/src/main/java/com/google/sps/Event.java b/walkthroughs/week-5-tdd/project/src/main/java/com/google/sps/Event.java
index 87b1194..4185d57 100644
--- a/walkthroughs/week-5-tdd/project/src/main/java/com/google/sps/Event.java
+++ b/walkthroughs/week-5-tdd/project/src/main/java/com/google/sps/Event.java
@@ -23,7 +23,7 @@
  * Event is the container class for when a specific group of people are meeting and are therefore
  * busy. Events are considered read-only.
  */
-public final class Event {
+public final class Event implements Comparable<Event>{
   private final String title;
   private final TimeRange when;
   private final Set<String> attendees = new HashSet<>();
@@ -75,6 +75,9 @@ public Set<String> getAttendees() {
     // internal data.
     return Collections.unmodifiableSet(attendees);
   }
+  public int compareTo(Event eventB) {
+      return this.getWhen().start() - eventB.getWhen().start();
+  }
 
   @Override
   public int hashCode() {
diff --git a/walkthroughs/week-5-tdd/project/src/main/java/com/google/sps/FindMeetingQuery.java b/walkthroughs/week-5-tdd/project/src/main/java/com/google/sps/FindMeetingQuery.java
index dadf069..6ea072a 100644
--- a/walkthroughs/week-5-tdd/project/src/main/java/com/google/sps/FindMeetingQuery.java
+++ b/walkthroughs/week-5-tdd/project/src/main/java/com/google/sps/FindMeetingQuery.java
@@ -14,10 +14,73 @@
 
 package com.google.sps;
 
-import java.util.Collection;
+import java.util.*;
+import java.lang.Math;
 
 public final class FindMeetingQuery {
   public Collection<TimeRange> query(Collection<Event> events, MeetingRequest request) {
-    throw new UnsupportedOperationException("TODO: Implement this method.");
+    long duration = request.getDuration();
+    ArrayList<Event> allEvents = new ArrayList();
+    ArrayList<Event> allEventsOptional = new ArrayList();
+    Set<String> attendees = new HashSet<String>(request.getAttendees());
+    Set<String> allAttendeesOptional = new HashSet<String>(request.getAttendees());
+    allAttendeesOptional.addAll(request.getOptionalAttendees());
+    //Add all events that attendees go to
+    for (Event event : events) {
+        Set<String> curAttendees = new HashSet<String>(attendees);
+        Set<String> curAttendeesOptional = new HashSet<String>(allAttendeesOptional);
+        curAttendees.retainAll(event.getAttendees());
+        curAttendeesOptional.retainAll(event.getAttendees());
+        if (!(curAttendees.isEmpty())){
+            allEvents.add(event);    
+        } 
+        if(!(curAttendeesOptional.isEmpty())){
+            allEventsOptional.add(event);
+        }
+        
+    }
+    Collections.sort(allEvents);
+    Collections.sort(allEventsOptional);
+    ArrayList<TimeRange> timesOptional = getTimes(allEventsOptional, request);
+    if (!(timesOptional.isEmpty()) || request.getAttendees().size() == 0){
+        return timesOptional;
+    }
+    ArrayList<TimeRange> times = getTimes(allEvents, request);
+    return times;
+  }
+
+  private ArrayList<TimeRange> getTimes(ArrayList<Event> allEvents, MeetingRequest request) {
+    ArrayList<TimeRange> times = new ArrayList();
+    int start = 0;
+    Boolean cont = false;
+    for (int i = 0; i < allEvents.size(); i++) {
+        TimeRange curTime = allEvents.get(i).getWhen();
+        if (!cont) {
+            TimeRange curRange = TimeRange.fromStartEnd(start, curTime.start(), false);
+            if ((long) curRange.duration() >= request.getDuration()) {
+                times.add(curRange);
+            }
+        }
+        //If next event overlaps with current, make start the greater of the two events
+        if ((i != allEvents.size() - 1) && curTime.overlaps(allEvents.get(i+1).getWhen())) {
+            start = Math.max(curTime.end(), start);
+            cont = true;
+        } else {
+            //If it doesn't overlap check gap during next iteration
+            start = Math.max(curTime.end(), start);
+            cont = false;
+        }
+        //If last event check if end of day is a possible time
+        if (i == allEvents.size() - 1) {
+            TimeRange curRange = TimeRange.fromStartEnd(start, TimeRange.END_OF_DAY, true);
+            if ((long) curRange.duration() >= request.getDuration()) {
+                times.add(curRange);
+            }
+        }
+    }
+    if (allEvents.size() == 0 && request.getDuration() <= TimeRange.END_OF_DAY) {
+        times.add(TimeRange.fromStartEnd(TimeRange.START_OF_DAY, TimeRange.END_OF_DAY, true));
+    }
+    return times;
   }
 }
diff --git a/walkthroughs/week-5-tdd/project/src/test/java/com/google/sps/FindMeetingQueryTest.java b/walkthroughs/week-5-tdd/project/src/test/java/com/google/sps/FindMeetingQueryTest.java
index 9235153..666c071 100644
--- a/walkthroughs/week-5-tdd/project/src/test/java/com/google/sps/FindMeetingQueryTest.java
+++ b/walkthroughs/week-5-tdd/project/src/test/java/com/google/sps/FindMeetingQueryTest.java
@@ -34,6 +34,7 @@ public final class FindMeetingQueryTest {
   // Some people that we can use in our tests.
   private static final String PERSON_A = "Person A";
   private static final String PERSON_B = "Person B";
+  private static final String PERSON_C = "Person C";
 
   // All dates are the first day of the year 2020.
   private static final int TIME_0800AM = TimeRange.getTimeInMinutes(8, 0);
@@ -43,6 +44,7 @@ public final class FindMeetingQueryTest {
   private static final int TIME_1000AM = TimeRange.getTimeInMinutes(10, 0);
   private static final int TIME_1100AM = TimeRange.getTimeInMinutes(11, 00);
 
+  private static final int DURATION_15_MINUTES = 15;
   private static final int DURATION_30_MINUTES = 30;
   private static final int DURATION_60_MINUTES = 60;
   private static final int DURATION_90_MINUTES = 90;
@@ -270,5 +272,119 @@ public void notEnoughRoom() {
 
     Assert.assertEquals(expected, actual);
   }
+  @Test 
+  public void disregardOptionalAttendee() {
+    Collection<Event> events = Arrays.asList(
+        new Event("Event 1", TimeRange.fromStartDuration(TIME_0800AM, DURATION_30_MINUTES),
+            Arrays.asList(PERSON_A)),
+        new Event("Event 2", TimeRange.fromStartDuration(TIME_0900AM, DURATION_30_MINUTES),
+            Arrays.asList(PERSON_B)),
+        new Event("Event 3", TimeRange.fromStartDuration(TimeRange.START_OF_DAY, TimeRange.END_OF_DAY),
+            Arrays.asList(PERSON_C)));
+
+    MeetingRequest request =
+        new MeetingRequest(Arrays.asList(PERSON_A, PERSON_B), DURATION_30_MINUTES);
+    request.addOptionalAttendee(PERSON_C);
+    Collection<TimeRange> actual = query.query(events, request);
+    Collection<TimeRange> expected =
+        Arrays.asList(TimeRange.fromStartEnd(TimeRange.START_OF_DAY, TIME_0800AM, false),
+            TimeRange.fromStartEnd(TIME_0830AM, TIME_0900AM, false),
+            TimeRange.fromStartEnd(TIME_0930AM, TimeRange.END_OF_DAY, true));
+
+    Assert.assertEquals(expected, actual);
+  }
+  @Test
+  public void considerOptionalAttendee() {
+    Collection<Event> events = Arrays.asList(
+    new Event("Event 1", TimeRange.fromStartDuration(TIME_0800AM, DURATION_30_MINUTES),
+        Arrays.asList(PERSON_A)),
+    new Event("Event 2", TimeRange.fromStartDuration(TIME_0900AM, DURATION_30_MINUTES),
+        Arrays.asList(PERSON_B)),
+    new Event("Event 3", TimeRange.fromStartDuration(TIME_0830AM, DURATION_30_MINUTES),
+        Arrays.asList(PERSON_C)));
+
+    MeetingRequest request =
+        new MeetingRequest(Arrays.asList(PERSON_A, PERSON_B), DURATION_30_MINUTES);
+    request.addOptionalAttendee(PERSON_C);
+    Collection<TimeRange> actual = query.query(events, request);
+    Collection<TimeRange> expected =
+        Arrays.asList(TimeRange.fromStartEnd(TimeRange.START_OF_DAY, TIME_0800AM, false),
+            TimeRange.fromStartEnd(TIME_0930AM, TimeRange.END_OF_DAY, true));
+
+    Assert.assertEquals(expected, actual);
+  }
+  @Test 
+  public void disregardIfNoFit() {
+      // Have one person, but make it so that there is just enough room at one point in the day to
+    // have the meeting.
+    //
+    // Events  : |--A--|     |----A----|
+    // Day     : |---------------------|
+    // Options :       |-----|
+
+    Collection<Event> events = Arrays.asList(
+        new Event("Event 1", TimeRange.fromStartEnd(TimeRange.START_OF_DAY, TIME_0830AM, false),
+            Arrays.asList(PERSON_A)),
+        new Event("Event 2", TimeRange.fromStartEnd(TIME_0900AM, TimeRange.END_OF_DAY, true),
+            Arrays.asList(PERSON_A)),
+        new Event("Event 3", TimeRange.fromStartDuration(TIME_0830AM, DURATION_15_MINUTES),
+            Arrays.asList(PERSON_B))    
+    );
+
+    MeetingRequest request = new MeetingRequest(Arrays.asList(PERSON_A), DURATION_30_MINUTES);
+    request.addOptionalAttendee(PERSON_B);
+    Collection<TimeRange> actual = query.query(events, request);
+    Collection<TimeRange> expected =
+        Arrays.asList(TimeRange.fromStartDuration(TIME_0830AM, DURATION_30_MINUTES));
+
+    Assert.assertEquals(expected, actual);
+  }
+
+  @Test
+  public void onlyOptionalFit() {
+    // Have one person, but make it so that there is just enough room at one point in the day to
+    // have the meeting.
+    //
+    // Events  : |--A--|     |----A----|
+    // Day     : |---------------------|
+    // Options :       |-----|
+
+    Collection<Event> events = Arrays.asList(
+        new Event("Event 1", TimeRange.fromStartEnd(TimeRange.START_OF_DAY, TIME_0830AM, false),
+            Arrays.asList(PERSON_A)),
+        new Event("Event 2", TimeRange.fromStartEnd(TIME_0900AM, TimeRange.END_OF_DAY, true),
+            Arrays.asList(PERSON_B))
+    );
+    MeetingRequest request = new MeetingRequest(Arrays.asList(), DURATION_30_MINUTES);
+    request.addOptionalAttendee(PERSON_A);
+    request.addOptionalAttendee(PERSON_B);
+    Collection<TimeRange> actual = query.query(events, request);
+    Collection<TimeRange> expected =
+        Arrays.asList(TimeRange.fromStartDuration(TIME_0830AM, DURATION_30_MINUTES));
+    Assert.assertEquals(expected, actual);
+  }
+  @Test
+  public void noMandatoryAttendeesConflict() {
+    // Have one person, but make it so that there is not enough room at any point in the day to
+    // have the meeting.
+    //
+    // Events  : |--A-----| |-----A----|
+    // Day     : |---------------------|
+    // Options :
+
+    Collection<Event> events = Arrays.asList(
+        new Event("Event 1", TimeRange.fromStartEnd(TimeRange.START_OF_DAY, TIME_0830AM, false),
+            Arrays.asList(PERSON_A)),
+        new Event("Event 2", TimeRange.fromStartEnd(TIME_0900AM, TimeRange.END_OF_DAY, true),
+            Arrays.asList(PERSON_A)));
+
+    MeetingRequest request = new MeetingRequest(Arrays.asList(), DURATION_60_MINUTES);
+    request.addOptionalAttendee(PERSON_A);
+    Collection<TimeRange> actual = query.query(events, request);
+    Collection<TimeRange> expected = Arrays.asList();
+
+    Assert.assertEquals(expected, actual);
+  }
+
 }