diff --git a/src/main/java/seedu/address/logic/commands/EditCommand.java b/src/main/java/seedu/address/logic/commands/EditCommand.java
index 2d07ca9a7e2..3a803e084aa 100644
--- a/src/main/java/seedu/address/logic/commands/EditCommand.java
+++ b/src/main/java/seedu/address/logic/commands/EditCommand.java
@@ -1,6 +1,7 @@
 package seedu.address.logic.commands;
 
 import static java.util.Objects.requireNonNull;
+import static seedu.address.logic.parser.CliSyntax.NIL_FIELD;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_ADDRESS;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_CCA;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_EMAIL;
@@ -55,7 +56,9 @@ public class EditCommand extends Command {
             + "[" + PREFIX_METADATA + "Meta-data]...\n"
             + "Example: " + COMMAND_WORD + " 1 "
             + PREFIX_PHONE + "91234567 "
-            + PREFIX_EMAIL + "johndoe@example.com";
+            + PREFIX_EMAIL + "johndoe@example.com\n\n"
+            + "Tip: To clear all of the person's roles, use " + PREFIX_ROLE + NIL_FIELD + "\n"
+            + "Tip: To clear all of the person's CCAs, use " + PREFIX_CCA + NIL_FIELD;
 
     public static final String MESSAGE_EDIT_PERSON_SUCCESS = "Edited Person: %1$s";
     public static final String MESSAGE_NOT_EDITED = "At least one field to edit must be provided.";
diff --git a/src/main/java/seedu/address/logic/parser/CliSyntax.java b/src/main/java/seedu/address/logic/parser/CliSyntax.java
index 38bd2d376f8..4ab30096a8c 100644
--- a/src/main/java/seedu/address/logic/parser/CliSyntax.java
+++ b/src/main/java/seedu/address/logic/parser/CliSyntax.java
@@ -16,4 +16,6 @@ public class CliSyntax {
     public static final Prefix PREFIX_ATTENDANCE = new Prefix("att/");
     public static final Prefix PREFIX_SESSIONS = new Prefix("s/");
     public static final Prefix PREFIX_METADATA = new Prefix("d/");
+
+    public static final String NIL_FIELD = "nil";
 }
diff --git a/src/main/java/seedu/address/logic/parser/EditCommandParser.java b/src/main/java/seedu/address/logic/parser/EditCommandParser.java
index 575277c1579..b514399addf 100644
--- a/src/main/java/seedu/address/logic/parser/EditCommandParser.java
+++ b/src/main/java/seedu/address/logic/parser/EditCommandParser.java
@@ -2,6 +2,7 @@
 
 import static java.util.Objects.requireNonNull;
 import static seedu.address.logic.Messages.MESSAGE_INVALID_PERSON_DISPLAYED_INDEX;
+import static seedu.address.logic.parser.CliSyntax.NIL_FIELD;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_ADDRESS;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_CCA;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_EMAIL;
@@ -89,7 +90,7 @@ private Optional<Set<Role>> parseRolesForEdit(Collection<String> roles) throws P
         if (roles.isEmpty()) {
             return Optional.empty();
         }
-        Collection<String> roleSet = roles.size() == 1 && roles.contains("") ? Collections.emptySet() : roles;
+        Collection<String> roleSet = roles.size() == 1 && roles.contains(NIL_FIELD) ? Collections.emptySet() : roles;
         return Optional.of(ParserUtil.parseRoles(roleSet));
     }
 
@@ -104,7 +105,7 @@ private Optional<Set<Cca>> parseCcasForEdit(Collection<String> ccas) throws Pars
         if (ccas.isEmpty()) {
             return Optional.empty();
         }
-        Collection<String> ccaSet = ccas.size() == 1 && ccas.contains("") ? Collections.emptySet() : ccas;
+        Collection<String> ccaSet = ccas.size() == 1 && ccas.contains(NIL_FIELD) ? Collections.emptySet() : ccas;
         return Optional.of(ParserUtil.parseCcas(ccaSet));
     }
 }
diff --git a/src/main/java/seedu/address/model/cca/Cca.java b/src/main/java/seedu/address/model/cca/Cca.java
index 58de0819e14..164f8b96808 100644
--- a/src/main/java/seedu/address/model/cca/Cca.java
+++ b/src/main/java/seedu/address/model/cca/Cca.java
@@ -2,6 +2,7 @@
 
 import static java.util.Objects.requireNonNull;
 import static seedu.address.commons.util.AppUtil.checkArgument;
+import static seedu.address.logic.parser.CliSyntax.NIL_FIELD;
 
 /**
  * Represents a CCA in the address book.
@@ -9,8 +10,10 @@
  */
 public class Cca {
 
-    public static final String MESSAGE_CONSTRAINTS = "CCA names should be alphanumeric (but can include "
-        + "whitespace)";
+    public static final String MESSAGE_CONSTRAINTS = "CCA names should be non-empty and alphanumeric "
+        + "(but can include whitespace).\n"
+        + "CCA names cannot be \"" + NIL_FIELD + "\" as \"" + NIL_FIELD
+        + "\" is reserved for denoting an empty CCA field.";
     public static final String VALIDATION_REGEX = "[\\p{Alnum}\\s]+";
 
     public final String ccaName;
@@ -30,7 +33,7 @@ public Cca(String ccaName) {
      * Returns true if a given string is a valid Cca name.
      */
     public static boolean isValidCcaName(String test) {
-        return test.matches(VALIDATION_REGEX);
+        return !test.equals(NIL_FIELD) && test.matches(VALIDATION_REGEX);
     }
 
     /**
diff --git a/src/main/java/seedu/address/model/roles/Role.java b/src/main/java/seedu/address/model/roles/Role.java
index 59ef7c7dbef..3d4f084176b 100644
--- a/src/main/java/seedu/address/model/roles/Role.java
+++ b/src/main/java/seedu/address/model/roles/Role.java
@@ -2,6 +2,7 @@
 
 import static java.util.Objects.requireNonNull;
 import static seedu.address.commons.util.AppUtil.checkArgument;
+import static seedu.address.logic.parser.CliSyntax.NIL_FIELD;
 
 /**
  * Represents a Role in the address book.
@@ -9,7 +10,10 @@
  */
 public class Role {
 
-    public static final String MESSAGE_CONSTRAINTS = "Role names should be alphanumeric with whitespace";
+    public static final String MESSAGE_CONSTRAINTS = "Role names should be non-empty and alphanumeric "
+        + "(but can include whitespace).\n"
+        + "Role names cannot be \"" + NIL_FIELD + "\" as \"" + NIL_FIELD
+        + "\" is reserved for denoting an empty role field.";
     public static final String VALIDATION_REGEX = "[\\p{Alnum}\\s]+";
 
     public final String roleName;
@@ -29,7 +33,7 @@ public Role(String roleName) {
      * Returns true if a given string is a valid role name.
      */
     public static boolean isValidRoleName(String test) {
-        return test.matches(VALIDATION_REGEX);
+        return !test.equals(NIL_FIELD) && test.matches(VALIDATION_REGEX);
     }
 
     @Override
diff --git a/src/test/java/seedu/address/testutil/PersonUtil.java b/src/test/java/seedu/address/testutil/PersonUtil.java
index b7b8d7cc2d1..c580e6ebf0b 100644
--- a/src/test/java/seedu/address/testutil/PersonUtil.java
+++ b/src/test/java/seedu/address/testutil/PersonUtil.java
@@ -1,5 +1,6 @@
 package seedu.address.testutil;
 
+import static seedu.address.logic.parser.CliSyntax.NIL_FIELD;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_ADDRESS;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_CCA;
 import static seedu.address.logic.parser.CliSyntax.PREFIX_EMAIL;
@@ -63,7 +64,7 @@ public static String getEditPersonDescriptorDetails(EditPersonDescriptor descrip
         if (descriptor.getRoles().isPresent()) {
             Set<Role> roles = descriptor.getRoles().get();
             if (roles.isEmpty()) {
-                sb.append(PREFIX_ROLE);
+                sb.append(PREFIX_ROLE + NIL_FIELD);
             } else {
                 sb.append(PREFIX_ROLE);
                 roles.forEach(s -> sb.append(PREFIX_ROLE).append(s.roleName).append(" "));
@@ -73,7 +74,7 @@ public static String getEditPersonDescriptorDetails(EditPersonDescriptor descrip
         if (descriptor.getCcas().isPresent()) {
             Set<Cca> roles = descriptor.getCcas().get();
             if (roles.isEmpty()) {
-                sb.append(PREFIX_CCA);
+                sb.append(PREFIX_CCA + NIL_FIELD);
             } else {
                 roles.forEach(s -> sb.append(PREFIX_CCA).append(s.ccaName).append(" "));
             }