diff --git a/processor/src/clients/mockPaymentAPI.ts b/processor/src/clients/mockPaymentAPI.ts
index ff6e761..6cf6a7c 100644
--- a/processor/src/clients/mockPaymentAPI.ts
+++ b/processor/src/clients/mockPaymentAPI.ts
@@ -1,6 +1,10 @@
 import { v4 as uuid } from 'uuid';
-import { CreatePaymentRequest, MockPaymentProviderResponse } from '../services/types/payment.type';
-import { PaymentOutcome } from '../dtos/payment.dto';
+import {
+  CreatePaymentRequest, MockPaymentProviderModificationResponse,
+  MockPaymentProviderResponse
+} from '../services/types/payment.type';
+import { PaymentModificationStatus, PaymentOutcome } from '../dtos/payment.dto';
+import { Payment } from '@commercetools/platform-sdk';
 
 // TODO: Make it class , add interface and provide implementation
 export const paymentProviderApi = (): any => {
@@ -20,9 +24,30 @@ export const paymentProviderApi = (): any => {
     };
   };
 
+  const cancelAuthorisedPaymentByPspReference =
+      async (pspReference: string, payment: Payment): Promise<MockPaymentProviderModificationResponse> => {
+
+    return { outcome: PaymentModificationStatus.RECEIVED, pspReference: pspReference }
+  }
+
+  const captureAuthorisedPayment =
+      async (pspReference: string, payment: Payment): Promise<MockPaymentProviderModificationResponse> => {
+
+    return { outcome: PaymentModificationStatus.RECEIVED, pspReference: pspReference }
+  }
+
+  const refundCapturedPayment =
+      async (pspReference: string, payment: Payment): Promise<MockPaymentProviderModificationResponse> => {
+
+    return { outcome: PaymentModificationStatus.RECEIVED, pspReference: pspReference }
+  }
+
   const isCreditCardAllowed = (cardNumber: string) => allowedCreditCards.includes(cardNumber);
 
   return {
     processPayment,
+    cancelAuthorisedPaymentByPspReference,
+    captureAuthorisedPayment,
+    refundCapturedPayment,
   };
 };
diff --git a/processor/src/dtos/payment.dto.ts b/processor/src/dtos/payment.dto.ts
index a340921..a033622 100644
--- a/processor/src/dtos/payment.dto.ts
+++ b/processor/src/dtos/payment.dto.ts
@@ -27,5 +27,31 @@ export const PaymentResponseSchema = Type.Object({
   paymentReference: Type.String(),
 });
 
+export const CapturePaymentRequestSchema = Type.Object({
+  amount: Type.Object({
+    centAmount: Type.Number(),
+    currencyCode: Type.String(),
+  }),
+});
+
+export const RefundPaymentRequestSchema = Type.Object({
+  amount: Type.Object({
+    centAmount: Type.Number(),
+    currencyCode: Type.String(),
+  }),
+});
+
+export enum PaymentModificationStatus {
+  RECEIVED = 'received',
+}
+const PaymentModificationSchema = Type.Enum(PaymentModificationStatus);
+
+export const PaymentModificationResponseSchema = Type.Object({
+  status: PaymentModificationSchema,
+});
+
 export type PaymentRequestSchemaDTO = Static<typeof PaymentRequestSchema>;
 export type PaymentResponseSchemaDTO = Static<typeof PaymentResponseSchema>;
+export type CapturePaymentRequestDTO = Static<typeof CapturePaymentRequestSchema>;
+export type RefundPaymentRequestDTO = Static<typeof RefundPaymentRequestSchema>;
+export type PaymentModificationResponseDTO = Static<typeof PaymentModificationResponseSchema>;
diff --git a/processor/src/routes/payment-modification.route.ts b/processor/src/routes/payment-modification.route.ts
new file mode 100644
index 0000000..a01c038
--- /dev/null
+++ b/processor/src/routes/payment-modification.route.ts
@@ -0,0 +1,53 @@
+import { FastifyInstance, FastifyPluginOptions } from 'fastify';
+import { PaymentService } from '../services/types/payment.type';
+import { CapturePaymentRequestDTO, PaymentModificationResponseDTO, RefundPaymentRequestDTO } from '../dtos/payment.dto';
+
+type PaymentRoutesOptions = {
+  paymentService: PaymentService;
+};
+
+export const paymentModificationRoutes = async (
+  fastify: FastifyInstance,
+  opts: FastifyPluginOptions & PaymentRoutesOptions,
+) => {
+  fastify.post<{ Body: any; Reply: PaymentModificationResponseDTO }>(
+    '/payments/:id/cancels',
+    {},
+    async (request, reply) => {
+      const params = request.params as any;
+      const resp = await opts.paymentService.cancelPayment({
+        paymentId: params.id,
+      });
+
+      return reply.status(200).send(resp);
+    },
+  );
+
+  fastify.post<{ Body: CapturePaymentRequestDTO; Reply: PaymentModificationResponseDTO }>(
+    '/payments/:id/captures',
+    {},
+    async (request, reply) => {
+      const params = request.params as any;
+      const resp = await opts.paymentService.capturePayment({
+        paymentId: params.id,
+        data: request.body,
+      });
+
+      return reply.status(200).send(resp);
+    },
+  );
+
+  fastify.post<{ Body: RefundPaymentRequestDTO; Reply: PaymentModificationResponseDTO }>(
+    '/payments/:id/refunds',
+    {},
+    async (request, reply) => {
+      const params = request.params as any;
+      const resp = await opts.paymentService.refundPayment({
+        paymentId: params.id,
+        data: request.body,
+      });
+
+      return reply.status(200).send(resp);
+    },
+  );
+};
diff --git a/processor/src/server.ts b/processor/src/server.ts
index d0931f8..725559e 100644
--- a/processor/src/server.ts
+++ b/processor/src/server.ts
@@ -10,6 +10,7 @@ import { configRoutes } from './routes/config.route';
 import { paymentRoutes } from './routes/payment.route';
 import { statusRoutes } from './routes/status.route';
 import { DefaultPaymentService } from './services/payment.service';
+import {paymentModificationRoutes} from "./routes/payment-modification.route";
 
 /**
  * Setup Fastify server instance
@@ -54,6 +55,9 @@ export const setupFastify = async () => {
     paymentService,
     sessionAuthHook: paymentSDK.sessionAuthHookFn,
   });
+  await server.register(paymentModificationRoutes, {
+    paymentService,
+  });
 
   return server;
 };
diff --git a/processor/src/services/payment.service.ts b/processor/src/services/payment.service.ts
index f699741..2d3d090 100644
--- a/processor/src/services/payment.service.ts
+++ b/processor/src/services/payment.service.ts
@@ -1,7 +1,18 @@
 import { CommercetoolsCartService, CommercetoolsPaymentService } from '@commercetools/connect-payments-sdk';
 import { paymentProviderApi } from '../clients/mockPaymentAPI';
-import { CreatePayment, PaymentService, PaymentServiceOptions } from './types/payment.type';
-import { PaymentOutcome, PaymentResponseSchemaDTO } from '../dtos/payment.dto';
+import {
+  CancelPayment,
+  CapturePayment,
+  CreatePayment,
+  PaymentService,
+  PaymentServiceOptions, RefundPayment
+} from './types/payment.type';
+import {
+  PaymentModificationResponseDTO,
+  PaymentModificationStatus,
+  PaymentOutcome,
+  PaymentResponseSchemaDTO
+} from '../dtos/payment.dto';
 import { getCartIdFromContext } from '../libs/fastify/context/context';
 
 export class DefaultPaymentService implements PaymentService {
@@ -69,6 +80,119 @@ export class DefaultPaymentService implements PaymentService {
     };
   }
 
+  public async cancelPayment(opts: CancelPayment): Promise<PaymentModificationResponseDTO> {
+    const ctPayment = await this.ctPaymentService.getPayment({
+      id: opts.paymentId,
+    });
+
+    await this.ctPaymentService.updatePayment({
+      id: ctPayment.id,
+      transaction: {
+        type: 'CancelAuthorization',
+        amount: ctPayment.amountPlanned,
+        state: 'Initial',
+      },
+    });
+
+    const res = await paymentProviderApi().cancelAuthorisedPaymentByPspReference(
+        ctPayment.interfaceId as string,
+        ctPayment,
+    );
+
+    await this.ctPaymentService.updatePayment({
+      id: ctPayment.id,
+      transaction: {
+        type: 'CancelAuthorization',
+        amount: ctPayment.amountPlanned,
+        interactionId: res.pspReference,
+        state: 'Pending',
+      },
+    });
+
+    return {
+      status: PaymentModificationStatus.RECEIVED,
+    };
+  }
+
+  public async capturePayment(opts: CapturePayment): Promise<PaymentModificationResponseDTO> {
+    const ctPayment = await this.ctPaymentService.getPayment({
+      id: opts.paymentId,
+    });
+
+    const data = { payment: ctPayment, data: opts.data };
+
+    await this.ctPaymentService.updatePayment({
+      id: ctPayment.id,
+      transaction: {
+        type: 'Charge',
+        amount: {
+          currencyCode: opts.data.amount.currencyCode,
+          centAmount: opts.data.amount.centAmount,
+        },
+        state: 'Initial',
+      },
+    });
+
+    const res = await paymentProviderApi().captureAuthorisedPayment(ctPayment.interfaceId as string, ctPayment);
+
+    await this.ctPaymentService.updatePayment({
+      id: ctPayment.id,
+      transaction: {
+        type: 'Charge',
+        amount: {
+          currencyCode: opts.data.amount.currencyCode,
+          centAmount: opts.data.amount.centAmount,
+        },
+        interactionId: res.pspReference,
+        state: 'Pending',
+      },
+    });
+
+    return {
+      status: PaymentModificationStatus.RECEIVED,
+    };
+  }
+
+  public async refundPayment(opts: RefundPayment): Promise<PaymentModificationResponseDTO> {
+    const ctPayment = await this.ctPaymentService.getPayment({
+      id: opts.paymentId,
+    });
+
+    const data = { payment: ctPayment, data: opts.data };
+
+    await this.ctPaymentService.updatePayment({
+      id: ctPayment.id,
+      transaction: {
+        type: 'Refund',
+        amount: {
+          currencyCode: opts.data.amount.currencyCode,
+          centAmount: opts.data.amount.centAmount,
+        },
+        state: 'Initial',
+      },
+    });
+
+    const res = await paymentProviderApi().refundCapturedPayment(ctPayment.interfaceId as string, ctPayment);
+
+    await this.ctPaymentService.updatePayment({
+      id: ctPayment.id,
+      transaction: {
+        type: 'Refund',
+        amount: {
+          currencyCode: opts.data.amount.currencyCode,
+          centAmount: opts.data.amount.centAmount,
+        },
+        interactionId: res.pspReference,
+        state: 'Pending',
+      },
+    });
+
+    return {
+      status: PaymentModificationStatus.RECEIVED,
+    };
+  }
+
+
   private convertPaymentResultCode(resultCode: PaymentOutcome): string {
     switch (resultCode) {
       case PaymentOutcome.AUTHORIZED:
diff --git a/processor/src/services/types/payment.type.ts b/processor/src/services/types/payment.type.ts
index c3b9144..d6ec0eb 100644
--- a/processor/src/services/types/payment.type.ts
+++ b/processor/src/services/types/payment.type.ts
@@ -1,6 +1,14 @@
 import { Cart, Payment } from '@commercetools/platform-sdk';
 import { CommercetoolsCartService, CommercetoolsPaymentService } from '@commercetools/connect-payments-sdk';
-import { PaymentOutcome, PaymentRequestSchemaDTO, PaymentResponseSchemaDTO } from '../../dtos/payment.dto';
+import {
+  CapturePaymentRequestDTO,
+  PaymentModificationResponseDTO,
+  PaymentModificationStatus,
+  PaymentOutcome,
+  PaymentRequestSchemaDTO,
+  PaymentResponseSchemaDTO,
+  RefundPaymentRequestDTO
+} from '../../dtos/payment.dto';
 
 export type CreatePayment = {
   data: PaymentRequestSchemaDTO;
@@ -18,8 +26,30 @@ export type MockPaymentProviderResponse = {
   paymentMethodType: string;
 };
 
+export type MockPaymentProviderModificationResponse = {
+  outcome: PaymentModificationStatus;
+  pspReference: string;
+};
+
+export type CancelPayment = {
+  paymentId: string;
+};
+
+export type CapturePayment = {
+  paymentId: string;
+  data: CapturePaymentRequestDTO;
+};
+
+export type RefundPayment = {
+  paymentId: string;
+  data: RefundPaymentRequestDTO;
+};
+
 export interface PaymentService {
   createPayment(opts: CreatePayment): Promise<PaymentResponseSchemaDTO>;
+  cancelPayment(opts: CancelPayment): Promise<PaymentModificationResponseDTO>;
+  capturePayment(opts: CapturePayment): Promise<PaymentModificationResponseDTO>;
+  refundPayment(opts: RefundPayment): Promise<PaymentModificationResponseDTO>;
 }
 
 export type PaymentServiceOptions = {